feat(web): login, first-run setup, org settings; org-aware AuthProvider

- Route group (app) holds AuthProvider + Sidebar, so /login and /setup
  render without app chrome and never mount the provider.
- AuthProvider drops the removed auth_enabled flag and exposes
  {user, org, isAdmin}.
- New login page (password + SSO), first-run setup page, and org settings
  page with a members table and the OIDC provider form.
- Settings page and the Organization nav entry are gated on role, since
  /api/settings now 403s for members.
- GET /api/org/oidc gains client_secret_set so the UI can show whether a
  secret is stored; the secret itself is still never serialized, and an
  empty submitted value still means "keep the stored one".
- Fix logout: the sidebar linked to /auth/logout with a GET, but the route
  is POST-only, so logout was 404ing.

web/app/(app)/layout.tsx

@@ -0,0 +1,17 @@
+import { AuthProvider } from "@/components/AuthProvider";
+import { Sidebar } from "@/components/Sidebar";
+
+export default function AppLayout({
+  children,
+}: {
+  children: React.ReactNode;
+}) {
+  return (
+    <AuthProvider>
+      <div className="flex h-screen overflow-hidden">
+        <Sidebar />
+        <main className="flex-1 overflow-y-auto">{children}</main>
+      </div>
+    </AuthProvider>
+  );
+}

web/app/(app)/settings/org/page.tsx

@@ -0,0 +1,400 @@
+"use client";
+
+import { useEffect, useState } from "react";
+import { useMutation, useQuery, useQueryClient } from "@tanstack/react-query";
+import { api, auth as authApi, type OrgUser, type Role } from "@/lib/api";
+import { useAuth } from "@/components/AuthProvider";
+import { Badge, Button, Card, Modal, Table, Tbody, Td, Th, Thead, Tr } from "@/components/ui";
+
+const ROLES: Role[] = ["owner", "admin", "member"];
+
+const inputClass =
+  "w-full rounded-lg border border-border bg-surface-2 px-3 py-2 text-sm text-text-primary focus:border-accent/50 focus:outline-none focus:ring-1 focus:ring-accent/30";
+
+function Field({ label, hint, children }: { label: string; hint?: string; children: React.ReactNode }) {
+  return (
+    <div>
+      <label className="mb-1.5 block text-sm font-medium text-text-secondary">{label}</label>
+      {children}
+      {hint && <p className="mt-1 text-xs text-text-tertiary">{hint}</p>}
+    </div>
+  );
+}
+
+function roleVariant(role: Role) {
+  if (role === "owner") return "accent" as const;
+  if (role === "admin") return "warning" as const;
+  return "neutral" as const;
+}
+
+function MembersCard() {
+  const queryClient = useQueryClient();
+  const { user } = useAuth();
+  const [addOpen, setAddOpen] = useState(false);
+  const [email, setEmail] = useState("");
+  const [password, setPassword] = useState("");
+  const [role, setRole] = useState<Role>("member");
+
+  const { data: users, isLoading, error } = useQuery({ queryKey: ["org-users"], queryFn: api.listOrgUsers });
+
+  const invalidate = () => queryClient.invalidateQueries({ queryKey: ["org-users"] });
+
+  const { mutate: createUser, isPending: creating, error: createError } = useMutation({
+    mutationFn: () => api.createOrgUser({ email, password, role }),
+    onSuccess: () => {
+      invalidate();
+      setAddOpen(false);
+      setEmail("");
+      setPassword("");
+      setRole("member");
+    },
+  });
+
+  const { mutate: changeRole } = useMutation({
+    mutationFn: ({ userId, next }: { userId: string; next: Role }) => api.updateOrgUserRole(userId, next),
+    onSuccess: invalidate,
+  });
+
+  const { mutate: removeUser } = useMutation({
+    mutationFn: (userId: string) => api.deleteOrgUser(userId),
+    onSuccess: invalidate,
+  });
+
+  return (
+    <Card>
+      <div className="mb-4 flex items-start justify-between gap-3">
+        <div>
+          <h2 className="text-base font-semibold text-text-primary">Members</h2>
+          <p className="mt-0.5 text-sm text-text-secondary">
+            People with access to this organization. Owners and admins can manage settings.
+          </p>
+        </div>
+        <Button variant="primary" size="sm" onClick={() => setAddOpen(true)}>
+          Add Member
+        </Button>
+      </div>
+
+      {isLoading ? (
+        <div className="flex justify-center py-8">
+          <div className="h-6 w-6 animate-spin rounded-full border-2 border-border border-t-accent" />
+        </div>
+      ) : error ? (
+        <p className="py-6 text-sm text-danger">{(error as Error).message}</p>
+      ) : !users || users.length === 0 ? (
+        <p className="py-6 text-sm text-text-secondary">No members yet.</p>
+      ) : (
+        <Table>
+          <Thead>
+            <Tr>
+              <Th>Email</Th>
+              <Th>Role</Th>
+              <Th>Sign-in</Th>
+              <Th>Last login</Th>
+              <Th className="text-right">Actions</Th>
+            </Tr>
+          </Thead>
+          <Tbody>
+            {users.map((u: OrgUser) => {
+              const isSelf = u.user_id === user?.user_id;
+              return (
+                <Tr key={u.user_id}>
+                  <Td>
+                    <span className="font-medium">{u.email}</span>
+                    {isSelf && <span className="ml-2 text-xs text-text-tertiary">(you)</span>}
+                  </Td>
+                  <Td>
+                    {isSelf ? (
+                      <Badge variant={roleVariant(u.role)}>{u.role}</Badge>
+                    ) : (
+                      <select
+                        value={u.role}
+                        onChange={(e) => changeRole({ userId: u.user_id, next: e.target.value as Role })}
+                        className="rounded-lg border border-border bg-surface-2 px-2 py-1 text-sm text-text-primary focus:border-accent/50 focus:outline-none"
+                      >
+                        {ROLES.map((r) => (
+                          <option key={r} value={r}>
+                            {r}
+                          </option>
+                        ))}
+                      </select>
+                    )}
+                  </Td>
+                  <Td>
+                    <Badge variant="neutral">{u.auth_source === "oidc" ? "SSO" : "Password"}</Badge>
+                  </Td>
+                  <Td className="text-text-secondary">
+                    {u.last_login ? new Date(u.last_login).toLocaleString() : "Never"}
+                  </Td>
+                  <Td className="text-right">
+                    {!isSelf && (
+                      <Button
+                        variant="ghost"
+                        size="sm"
+                        onClick={() => {
+                          if (confirm(`Remove ${u.email} from this organization?`)) removeUser(u.user_id);
+                        }}
+                      >
+                        Remove
+                      </Button>
+                    )}
+                  </Td>
+                </Tr>
+              );
+            })}
+          </Tbody>
+        </Table>
+      )}
+
+      <Modal open={addOpen} title="Add Member" onClose={() => setAddOpen(false)}>
+        <form
+          onSubmit={(e) => {
+            e.preventDefault();
+            createUser();
+          }}
+          className="space-y-4"
+        >
+          <Field label="Email">
+            <input
+              type="email"
+              required
+              value={email}
+              onChange={(e) => setEmail(e.target.value)}
+              className={inputClass}
+            />
+          </Field>
+
+          <Field
+            label="Password"
+            hint="Leave blank if this member will sign in through SSO instead."
+          >
+            <input
+              type="password"
+              autoComplete="new-password"
+              value={password}
+              onChange={(e) => setPassword(e.target.value)}
+              className={inputClass}
+            />
+          </Field>
+
+          <Field label="Role">
+            <select value={role} onChange={(e) => setRole(e.target.value as Role)} className={inputClass}>
+              {ROLES.map((r) => (
+                <option key={r} value={r}>
+                  {r}
+                </option>
+              ))}
+            </select>
+          </Field>
+
+          {createError && (
+            <div className="rounded-lg border border-danger/30 bg-danger/10 px-3 py-2 text-sm text-danger">
+              {(createError as Error).message}
+            </div>
+          )}
+
+          <div className="flex justify-end gap-2">
+            <Button type="button" variant="ghost" onClick={() => setAddOpen(false)}>
+              Cancel
+            </Button>
+            <Button type="submit" variant="primary" loading={creating}>
+              Add Member
+            </Button>
+          </div>
+        </form>
+      </Modal>
+    </Card>
+  );
+}
+
+function OIDCCard() {
+  const queryClient = useQueryClient();
+  const { data: cfg, isLoading } = useQuery({ queryKey: ["org-oidc"], queryFn: api.getOrgOIDC });
+
+  const [issuer, setIssuer] = useState("");
+  const [clientId, setClientId] = useState("");
+  const [clientSecret, setClientSecret] = useState("");
+  const [enabled, setEnabled] = useState(false);
+  const [saved, setSaved] = useState(false);
+  const [copied, setCopied] = useState(false);
+
+  const redirectUrl = authApi.oidcRedirectUrl();
+
+  useEffect(() => {
+    if (!cfg) return;
+    setIssuer(cfg.issuer ?? "");
+    setClientId(cfg.client_id ?? "");
+    setEnabled(cfg.enabled);
+    // The secret is never returned; leave the field blank to mean "unchanged".
+    setClientSecret("");
+  }, [cfg]);
+
+  const { mutate: save, isPending, error } = useMutation({
+    mutationFn: () => api.saveOrgOIDC({ issuer, client_id: clientId, client_secret: clientSecret, enabled }),
+    onSuccess: () => {
+      queryClient.invalidateQueries({ queryKey: ["org-oidc"] });
+      setClientSecret("");
+      setSaved(true);
+      setTimeout(() => setSaved(false), 3000);
+    },
+  });
+
+  async function copyRedirect() {
+    await navigator.clipboard.writeText(redirectUrl);
+    setCopied(true);
+    setTimeout(() => setCopied(false), 2000);
+  }
+
+  if (isLoading) {
+    return (
+      <Card>
+        <div className="flex justify-center py-8">
+          <div className="h-6 w-6 animate-spin rounded-full border-2 border-border border-t-accent" />
+        </div>
+      </Card>
+    );
+  }
+
+  const secretSet = cfg?.client_secret_set ?? false;
+
+  return (
+    <Card>
+      <div className="mb-4">
+        <h2 className="text-base font-semibold text-text-primary">Single Sign-On (OIDC)</h2>
+        <p className="mt-0.5 text-sm text-text-secondary">
+          Let members sign in with your identity provider. Users are provisioned into this organization on
+          first sign-in.
+        </p>
+      </div>
+
+      <div className="mb-5 rounded-lg border border-border bg-surface-2 p-3">
+        <p className="mb-2 text-xs font-medium text-text-secondary">
+          Register this redirect URL with your provider:
+        </p>
+        <div className="flex items-center gap-2">
+          <code className="flex-1 overflow-x-auto rounded bg-background px-2 py-1.5 font-mono text-xs text-text-primary">
+            {redirectUrl}
+          </code>
+          <Button type="button" variant="ghost" size="sm" onClick={copyRedirect}>
+            {copied ? "Copied!" : "Copy"}
+          </Button>
+        </div>
+      </div>
+
+      <form
+        onSubmit={(e) => {
+          e.preventDefault();
+          save();
+        }}
+        className="space-y-4"
+      >
+        <Field label="Issuer URL" hint="The provider's OIDC discovery base, e.g. https://accounts.google.com">
+          <input
+            type="url"
+            required
+            value={issuer}
+            onChange={(e) => setIssuer(e.target.value)}
+            className={inputClass}
+          />
+        </Field>
+
+        <Field label="Client ID">
+          <input
+            type="text"
+            required
+            value={clientId}
+            onChange={(e) => setClientId(e.target.value)}
+            className={inputClass}
+          />
+        </Field>
+
+        <Field
+          label="Client Secret"
+          hint={
+            secretSet
+              ? "A secret is stored. Leave this blank to keep it, or enter a new one to replace it."
+              : "No secret stored yet."
+          }
+        >
+          <input
+            type="password"
+            autoComplete="new-password"
+            placeholder={secretSet ? "•••••••• (unchanged)" : "Enter client secret"}
+            value={clientSecret}
+            onChange={(e) => setClientSecret(e.target.value)}
+            className={inputClass}
+          />
+        </Field>
+
+        <div className="flex items-center gap-2 text-sm">
+          <span className={`inline-block h-2 w-2 rounded-full ${secretSet ? "bg-success" : "bg-text-tertiary"}`} />
+          <span className="text-text-secondary">
+            {secretSet ? "Client secret is configured" : "No client secret configured"}
+          </span>
+        </div>
+
+        <label className="flex items-center gap-2 text-sm text-text-secondary">
+          <input
+            type="checkbox"
+            checked={enabled}
+            onChange={(e) => setEnabled(e.target.checked)}
+            className="h-4 w-4 rounded border-border bg-surface-2 accent-accent"
+          />
+          Enable SSO sign-in for this organization
+        </label>
+
+        {enabled && !secretSet && !clientSecret && (
+          <div className="rounded-lg border border-warning/30 bg-warning/10 px-3 py-2 text-sm text-warning">
+            SSO cannot complete sign-in without a client secret.
+          </div>
+        )}
+
+        {error && (
+          <div className="rounded-lg border border-danger/30 bg-danger/10 px-3 py-2 text-sm text-danger">
+            {(error as Error).message}
+          </div>
+        )}
+
+        <div className="flex items-center gap-3">
+          <Button type="submit" variant="primary" loading={isPending}>
+            {saved ? "Saved!" : "Save SSO Settings"}
+          </Button>
+          {saved && <span className="text-sm text-success">SSO settings saved.</span>}
+        </div>
+      </form>
+    </Card>
+  );
+}
+
+export default function OrgSettingsPage() {
+  const { org, isAdmin } = useAuth();
+
+  if (!isAdmin) {
+    return (
+      <div className="p-8">
+        <Card className="max-w-lg">
+          <h1 className="text-base font-semibold text-text-primary">You don&apos;t have access</h1>
+          <p className="mt-1 text-sm text-text-secondary">
+            Organization settings are available to owners and admins only. Ask an administrator if you need
+            access.
+          </p>
+        </Card>
+      </div>
+    );
+  }
+
+  return (
+    <div className="p-8">
+      <div className="mb-8">
+        <h1 className="text-2xl font-bold text-text-primary">Organization</h1>
+        <p className="mt-1 text-sm text-text-secondary">
+          {org ? `Manage members and sign-in for ${org.name}.` : "Manage members and sign-in."}
+        </p>
+      </div>
+
+      <div className="space-y-6">
+        <MembersCard />
+        <OIDCCard />
+      </div>
+    </div>
+  );
+}

web/app/(app)/settings/page.tsx

@@ -4,6 +4,7 @@ import { useEffect, useState } from "react";
 import { useQuery, useMutation, useQueryClient } from "@tanstack/react-query";
 import Link from "next/link";
 import { api } from "@/lib/api";
+import { useAuth } from "@/components/AuthProvider";
 import { Button, Card } from "@/components/ui";
 
 function SectionCard({ title, description, icon, children, className }: { title: string; description?: string; icon: React.ReactNode; children: React.ReactNode; className?: string }) {
@@ -136,8 +137,14 @@ function SecretsTokenCard({ tokenSet, rotatedAt }: { tokenSet: boolean; rotatedA
 
 export default function SettingsPage() {
     const queryClient = useQueryClient();
+    const { isAdmin } = useAuth();
 
-    const { data: settings, isLoading } = useQuery({ queryKey: ["settings"], queryFn: api.getSettings });
+    // /api/settings requires owner|admin and 403s for members, so don't even ask.
+    const { data: settings, isLoading } = useQuery({
+        queryKey: ["settings"],
+        queryFn: api.getSettings,
+        enabled: isAdmin,
+    });
 
     const [thresholdMinutes, setThresholdMinutes] = useState(5);
     const [logRetentionDays, setLogRetentionDays] = useState(30);
@@ -170,6 +177,19 @@ export default function SettingsPage() {
         });
     }
 
+    if (!isAdmin) {
+        return (
+            <div className="p-8">
+                <Card className="max-w-lg">
+                    <h1 className="text-base font-semibold text-text-primary">You don&apos;t have access</h1>
+                    <p className="mt-1 text-sm text-text-secondary">
+                        Settings are available to owners and admins only. Ask an administrator if you need access.
+                    </p>
+                </Card>
+            </div>
+        );
+    }
+
     if (isLoading) {
         return (
             <div className="flex h-full items-center justify-center">

web/app/layout.tsx

@@ -1,8 +1,6 @@
 import type { Metadata } from "next";
 import "./globals.css";
 import { Providers } from "@/components/Providers";
-import { AuthProvider } from "@/components/AuthProvider";
-import { Sidebar } from "@/components/Sidebar";
 
 export const metadata: Metadata = {
   title: "Vantage",
@@ -17,16 +15,7 @@ export default function RootLayout({
   return (
     <html lang="en" className="dark">
       <body className="bg-background text-text-primary">
-        <Providers>
-          <AuthProvider>
-            <div className="flex h-screen overflow-hidden">
-              <Sidebar />
-              <main className="flex-1 overflow-y-auto">
-                {children}
-              </main>
-            </div>
-          </AuthProvider>
-        </Providers>
+        <Providers>{children}</Providers>
       </body>
     </html>
   );

web/app/login/page.tsx

@@ -0,0 +1,109 @@
+"use client";
+
+import { useEffect, useState } from "react";
+import { useMutation } from "@tanstack/react-query";
+import { auth } from "@/lib/api";
+import { Button, Card } from "@/components/ui";
+
+export default function LoginPage() {
+  const [email, setEmail] = useState("");
+  const [password, setPassword] = useState("");
+
+  // If the instance has no users yet, first-run setup is the only way in.
+  useEffect(() => {
+    auth
+      .bootstrapStatus()
+      .then((s) => {
+        if (s.needs_setup) window.location.href = "/setup";
+      })
+      .catch(() => {
+        // Status unavailable — let the login form stand.
+      });
+  }, []);
+
+  const { mutate: signIn, isPending, error } = useMutation({
+    mutationFn: () => auth.login(email, password),
+    onSuccess: () => {
+      window.location.href = "/";
+    },
+  });
+
+  function handleSubmit(e: React.FormEvent) {
+    e.preventDefault();
+    signIn();
+  }
+
+  return (
+    <div className="flex min-h-screen items-center justify-center bg-background p-4">
+      <div className="w-full max-w-sm">
+        <div className="mb-8 flex flex-col items-center gap-3">
+          <div className="flex h-11 w-11 items-center justify-center rounded-xl bg-accent">
+            <svg className="h-6 w-6 text-white" fill="none" viewBox="0 0 24 24" stroke="currentColor" strokeWidth={2}>
+              <path strokeLinecap="round" strokeLinejoin="round" d="M15.75 5.25a3 3 0 013 3m3 0a6 6 0 01-7.029 5.912c-.563-.097-1.159.026-1.563.43L10.5 17.25H8.25v2.25H6v2.25H2.25v-2.818c0-.597.237-1.17.659-1.591l6.499-6.499c.404-.404.527-1 .43-1.563A6 6 0 1121.75 8.25z" />
+            </svg>
+          </div>
+          <h1 className="text-xl font-semibold text-text-primary">Sign in to Vantage</h1>
+        </div>
+
+        <Card>
+          <form onSubmit={handleSubmit} className="space-y-4">
+            <div>
+              <label htmlFor="email" className="mb-1.5 block text-sm font-medium text-text-secondary">
+                Email
+              </label>
+              <input
+                id="email"
+                type="email"
+                required
+                autoComplete="username"
+                value={email}
+                onChange={(e) => setEmail(e.target.value)}
+                className="w-full rounded-lg border border-border bg-surface-2 px-3 py-2 text-sm text-text-primary focus:border-accent/50 focus:outline-none focus:ring-1 focus:ring-accent/30"
+              />
+            </div>
+
+            <div>
+              <label htmlFor="password" className="mb-1.5 block text-sm font-medium text-text-secondary">
+                Password
+              </label>
+              <input
+                id="password"
+                type="password"
+                required
+                autoComplete="current-password"
+                value={password}
+                onChange={(e) => setPassword(e.target.value)}
+                className="w-full rounded-lg border border-border bg-surface-2 px-3 py-2 text-sm text-text-primary focus:border-accent/50 focus:outline-none focus:ring-1 focus:ring-accent/30"
+              />
+            </div>
+
+            {error && (
+              <div className="rounded-lg border border-danger/30 bg-danger/10 px-3 py-2 text-sm text-danger">
+                {(error as Error).message}
+              </div>
+            )}
+
+            <Button type="submit" variant="primary" loading={isPending} className="w-full justify-center">
+              Sign In
+            </Button>
+          </form>
+
+          <div className="my-5 flex items-center gap-3">
+            <div className="h-px flex-1 bg-border" />
+            <span className="text-xs uppercase tracking-wider text-text-tertiary">or</span>
+            <div className="h-px flex-1 bg-border" />
+          </div>
+
+          <a href="/auth/oidc/start" className="block">
+            <Button type="button" variant="secondary" className="w-full justify-center">
+              Sign in with your organization&apos;s SSO
+            </Button>
+          </a>
+          <p className="mt-3 text-center text-xs text-text-tertiary">
+            SSO must be enabled for this organization by an administrator.
+          </p>
+        </Card>
+      </div>
+    </div>
+  );
+}

web/app/setup/page.tsx

@@ -0,0 +1,169 @@
+"use client";
+
+import { useEffect, useState } from "react";
+import { useMutation } from "@tanstack/react-query";
+import { auth } from "@/lib/api";
+import { Button, Card } from "@/components/ui";
+
+const MIN_PASSWORD_LENGTH = 8;
+
+/**
+ * Org hosts are `<slug>.vantage.<rest>` and the apex is `vantage.<rest>` (see
+ * auth.hostSlug on the server). Build the new org's URL by prepending — or
+ * replacing — the leftmost label. Hosts that don't match that shape (localhost,
+ * bare IPs) have no per-org subdomain, so stay put.
+ */
+function orgUrlForSlug(slug: string): string {
+  if (typeof window === "undefined") return "/";
+  const { protocol, host } = window.location;
+  const [hostname, port] = host.split(":");
+  const parts = hostname.split(".");
+
+  if (parts.length < 2 || parts[parts.length - 1] === "localhost") return "/";
+
+  const rest = parts[0] === "vantage" ? parts : parts.slice(1);
+  if (rest[0] !== "vantage") return "/";
+
+  const newHost = [slug, ...rest].join(".") + (port ? `:${port}` : "");
+  return `${protocol}//${newHost}/`;
+}
+
+export default function SetupPage() {
+  const [orgName, setOrgName] = useState("");
+  const [email, setEmail] = useState("");
+  const [password, setPassword] = useState("");
+  const [confirm, setConfirm] = useState("");
+  const [validationError, setValidationError] = useState<string | null>(null);
+
+  // Setup is a one-shot route; once an owner exists it must not be reachable.
+  useEffect(() => {
+    auth
+      .bootstrapStatus()
+      .then((s) => {
+        if (!s.needs_setup) window.location.href = "/login";
+      })
+      .catch(() => {
+        // Status unavailable — let the form stand; the backend re-checks on submit.
+      });
+  }, []);
+
+  const { mutate: bootstrap, isPending, error } = useMutation({
+    mutationFn: () => auth.bootstrap({ org_name: orgName, email, password }),
+    onSuccess: (res) => {
+      window.location.href = orgUrlForSlug(res.slug);
+    },
+  });
+
+  function handleSubmit(e: React.FormEvent) {
+    e.preventDefault();
+    if (password.length < MIN_PASSWORD_LENGTH) {
+      setValidationError(`Password must be at least ${MIN_PASSWORD_LENGTH} characters.`);
+      return;
+    }
+    if (password !== confirm) {
+      setValidationError("Passwords do not match.");
+      return;
+    }
+    setValidationError(null);
+    bootstrap();
+  }
+
+  // Prefer the backend's message (it owns the real validation rules).
+  const message = validationError ?? (error ? (error as Error).message : null);
+
+  const inputClass =
+    "w-full rounded-lg border border-border bg-surface-2 px-3 py-2 text-sm text-text-primary focus:border-accent/50 focus:outline-none focus:ring-1 focus:ring-accent/30";
+
+  return (
+    <div className="flex min-h-screen items-center justify-center bg-background p-4">
+      <div className="w-full max-w-md">
+        <div className="mb-8 text-center">
+          <h1 className="text-xl font-semibold text-text-primary">Welcome to Vantage</h1>
+          <p className="mt-1 text-sm text-text-secondary">
+            Create your organization and its owner account to get started.
+          </p>
+        </div>
+
+        <Card>
+          <form onSubmit={handleSubmit} className="space-y-4">
+            <div>
+              <label htmlFor="org" className="mb-1.5 block text-sm font-medium text-text-secondary">
+                Organization name
+              </label>
+              <input
+                id="org"
+                type="text"
+                required
+                value={orgName}
+                onChange={(e) => setOrgName(e.target.value)}
+                className={inputClass}
+              />
+              <p className="mt-1 text-xs text-text-tertiary">
+                Used to derive your organization&apos;s subdomain.
+              </p>
+            </div>
+
+            <div>
+              <label htmlFor="email" className="mb-1.5 block text-sm font-medium text-text-secondary">
+                Owner email
+              </label>
+              <input
+                id="email"
+                type="email"
+                required
+                autoComplete="username"
+                value={email}
+                onChange={(e) => setEmail(e.target.value)}
+                className={inputClass}
+              />
+            </div>
+
+            <div>
+              <label htmlFor="password" className="mb-1.5 block text-sm font-medium text-text-secondary">
+                Password
+              </label>
+              <input
+                id="password"
+                type="password"
+                required
+                minLength={MIN_PASSWORD_LENGTH}
+                autoComplete="new-password"
+                value={password}
+                onChange={(e) => setPassword(e.target.value)}
+                className={inputClass}
+              />
+              <p className="mt-1 text-xs text-text-tertiary">
+                At least {MIN_PASSWORD_LENGTH} characters.
+              </p>
+            </div>
+
+            <div>
+              <label htmlFor="confirm" className="mb-1.5 block text-sm font-medium text-text-secondary">
+                Confirm password
+              </label>
+              <input
+                id="confirm"
+                type="password"
+                required
+                autoComplete="new-password"
+                value={confirm}
+                onChange={(e) => setConfirm(e.target.value)}
+                className={inputClass}
+              />
+            </div>
+
+            {message && (
+              <div className="rounded-lg border border-danger/30 bg-danger/10 px-3 py-2 text-sm text-danger">
+                {message}
+              </div>
+            )}
+
+            <Button type="submit" variant="primary" loading={isPending} className="w-full justify-center">
+              Create Organization
+            </Button>
+          </form>
+        </Card>
+      </div>
+    </div>
+  );
+}

web/components/AuthProvider.tsx

@@ -1,49 +1,63 @@
 "use client";
 
 import { createContext, useContext, useEffect, useState, ReactNode } from "react";
+import { auth, type Org, type Role, type SessionUser } from "@/lib/api";
 
-export interface User {
-  user_id: string;
-  email: string;
-  name: string;
-}
+export type { Org, Role, SessionUser };
 
 interface AuthContextType {
-  user: User | null;
-  authEnabled: boolean;
+  user: SessionUser | null;
+  org: Org | null;
+  /** True for owner and admin — the roles the /api/settings and /api/org routes require. */
+  isAdmin: boolean;
 }
 
-const AuthContext = createContext<AuthContextType>({ user: null, authEnabled: false });
+const AuthContext = createContext<AuthContextType>({ user: null, org: null, isAdmin: false });
 
 export function useAuth() {
   return useContext(AuthContext);
 }
 
+/**
+ * Wraps the authenticated app shell only (see app/(app)/layout.tsx). /login and
+ * /setup live outside the group, so no pathname guard is needed here.
+ */
 export function AuthProvider({ children }: { children: ReactNode }) {
-  const [user, setUser] = useState<User | null>(null);
-  const [authEnabled, setAuthEnabled] = useState(false);
+  const [user, setUser] = useState<SessionUser | null>(null);
+  const [org, setOrg] = useState<Org | null>(null);
   const [loading, setLoading] = useState(true);
 
   useEffect(() => {
-    fetch("/auth/me", { credentials: "include" })
-      .then(async (res) => {
-        if (res.status === 401) {
-          window.location.href = "/auth/login";
+    let cancelled = false;
+
+    (async () => {
+      try {
+        const status = await auth.bootstrapStatus();
+        if (status.needs_setup) {
+          window.location.href = "/setup";
           return;
         }
-        const data = await res.json();
-        if (data.auth_enabled === false) {
-          setAuthEnabled(false);
-        } else {
-          setAuthEnabled(true);
-          setUser(data as User);
+
+        const me = await auth.me();
+        if (cancelled) return;
+        setUser(me.user);
+        setOrg(me.org);
+        setLoading(false);
+      } catch (err) {
+        if (cancelled) return;
+        const status = (err as { status?: number }).status;
+        if (status === 401) {
+          window.location.href = "/login";
+          return;
         }
+        // Backend unreachable or unexpected failure — don't trap the user on a spinner.
         setLoading(false);
-      })
-      .catch(() => {
-        // Backend unreachable — don't block the UI
-        setLoading(false);
-      });
+      }
+    })();
+
+    return () => {
+      cancelled = true;
+    };
   }, []);
 
   if (loading) {
@@ -54,9 +68,9 @@ export function AuthProvider({ children }: { children: ReactNode }) {
     );
   }
 
+  const isAdmin = user?.role === "owner" || user?.role === "admin";
+
   return (
-    <AuthContext.Provider value={{ user, authEnabled }}>
-      {children}
-    </AuthContext.Provider>
+    <AuthContext.Provider value={{ user, org, isAdmin }}>{children}</AuthContext.Provider>
   );
 }

web/components/Sidebar.tsx

@@ -4,11 +4,14 @@ import Link from "next/link";
 import { usePathname } from "next/navigation";
 import { clsx } from "clsx";
 import { useAuth } from "@/components/AuthProvider";
+import { auth } from "@/lib/api";
 
 interface NavItem {
   href: string;
   label: string;
   icon: React.ReactNode;
+  /** Restricted to owner/admin — the roles the backing API requires. */
+  adminOnly?: boolean;
 }
 
 function ServerIcon() {
@@ -76,6 +79,14 @@ function StepsIcon() {
   );
 }
 
+function OrgIcon() {
+  return (
+    <svg className="h-5 w-5" fill="none" viewBox="0 0 24 24" stroke="currentColor" strokeWidth={1.5}>
+      <path strokeLinecap="round" strokeLinejoin="round" d="M3.75 21h16.5M4.5 3h15M5.25 3v18m13.5-18v18M9 6.75h1.5m-1.5 3h1.5m-1.5 3h1.5m3-6H15m-1.5 3H15m-1.5 3H15M9 21v-3.375c0-.621.504-1.125 1.125-1.125h3.75c.621 0 1.125.504 1.125 1.125V21" />
+    </svg>
+  );
+}
+
 const navItems: NavItem[] = [
   { href: "/servers", label: "Servers", icon: <ServerIcon /> },
   { href: "/monitors", label: "Monitors", icon: <MonitorIcon /> },
@@ -84,12 +95,32 @@ const navItems: NavItem[] = [
   { href: "/workflows", label: "Workflows", icon: <WorkflowIcon /> },
   { href: "/steps", label: "Steps", icon: <StepsIcon /> },
   { href: "/audit", label: "Audit Log", icon: <AuditIcon /> },
-  { href: "/settings", label: "Settings", icon: <SettingsIcon /> },
+  { href: "/settings/org", label: "Organization", icon: <OrgIcon />, adminOnly: true },
+  { href: "/settings", label: "Settings", icon: <SettingsIcon />, adminOnly: true },
 ];
 
 export function Sidebar() {
   const pathname = usePathname();
-  const { user, authEnabled } = useAuth();
+  const { user, org, isAdmin } = useAuth();
+
+  const visibleItems = navItems.filter((item) => !item.adminOnly || isAdmin);
+
+  // Longest match wins, so /settings/org doesn't also light up /settings.
+  const activeHref = visibleItems.reduce<string | null>((best, item) => {
+    const matches = pathname === item.href || pathname.startsWith(item.href + "/");
+    if (!matches) return best;
+    return best === null || item.href.length > best.length ? item.href : best;
+  }, null);
+
+  async function handleLogout() {
+    // /auth/logout is POST-only on the server.
+    try {
+      await auth.logout();
+    } catch {
+      // Fall through — clearing the client-side session view is what matters.
+    }
+    window.location.href = "/login";
+  }
 
   return (
     <aside className="flex h-screen w-60 flex-col border-r border-border bg-surface">
@@ -99,14 +130,16 @@ export function Sidebar() {
             <path strokeLinecap="round" strokeLinejoin="round" d="M15.75 5.25a3 3 0 013 3m3 0a6 6 0 01-7.029 5.912c-.563-.097-1.159.026-1.563.43L10.5 17.25H8.25v2.25H6v2.25H2.25v-2.818c0-.597.237-1.17.659-1.591l6.499-6.499c.404-.404.527-1 .43-1.563A6 6 0 1121.75 8.25z" />
           </svg>
         </div>
-        <span className="text-base font-semibold text-text-primary">Vantage</span>
+        <div className="min-w-0">
+          <span className="block text-base font-semibold leading-tight text-text-primary">Vantage</span>
+          {org && <span className="block truncate text-xs text-text-secondary">{org.name}</span>}
+        </div>
       </div>
 
       <nav className="flex-1 overflow-y-auto px-3 py-4">
         <ul className="space-y-1">
-          {navItems.map((item) => {
-            const isActive =
-              pathname === item.href || pathname.startsWith(item.href + "/");
+          {visibleItems.map((item) => {
+            const isActive = activeHref === item.href;
             return (
               <li key={item.href}>
                 <Link
@@ -128,21 +161,25 @@ export function Sidebar() {
       </nav>
 
       <div className="border-t border-border px-4 py-3">
-        {authEnabled && user && (
+        {user && (
           <div className="mb-3">
             <p className="truncate text-sm font-medium text-text-primary">{user.name || user.email}</p>
-            <p className="truncate text-xs text-text-secondary">{user.email}</p>
+            <p className="truncate text-xs text-text-secondary">
+              {user.email}
+              {user.role && <span className="ml-1 text-text-tertiary">· {user.role}</span>}
+            </p>
           </div>
         )}
         <div className="flex items-center justify-between">
           <p className="text-xs text-text-secondary">Vantage v1.0</p>
-          {authEnabled && user && (
-            <a
-              href="/auth/logout"
+          {user && (
+            <button
+              type="button"
+              onClick={handleLogout}
               className="text-xs text-text-secondary transition-colors hover:text-danger"
             >
               Logout
-            </a>
+            </button>
           )}
         </div>
       </div>

web/lib/api.ts

@@ -296,6 +296,74 @@ export interface WorkflowRun {
   server_runs: ServerRun[];
 }
 
+export type Role = "owner" | "admin" | "member";
+
+/** The session as returned by GET /auth/me — mirrors auth.Session on the server. */
+export interface SessionUser {
+  user_id: string;
+  org_id: string;
+  role: Role;
+  email: string;
+  name: string;
+}
+
+export interface Org {
+  org_id: string;
+  name: string;
+  slug: string;
+  created_at: string;
+}
+
+export interface MeResponse {
+  user: SessionUser;
+  org: Org | null;
+}
+
+export interface BootstrapStatus {
+  needs_setup: boolean;
+}
+
+export interface BootstrapResponse {
+  org: Org;
+  slug: string;
+}
+
+export interface OrgUser {
+  user_id: string;
+  org_id: string;
+  email: string;
+  role: Role;
+  auth_source: "local" | "oidc";
+  created_at: string;
+  last_login?: string;
+}
+
+export interface OrgUserInput {
+  email: string;
+  password: string;
+  role: Role;
+}
+
+/**
+ * GET /api/org/oidc. `client_secret_set` reports whether a secret is stored —
+ * the secret itself is write-only and is never returned. Submitting an empty
+ * `client_secret` on save keeps the stored one.
+ */
+export interface OrgOIDCConfig {
+  issuer?: string;
+  client_id?: string;
+  enabled: boolean;
+  client_secret_set: boolean;
+  updated_at?: string;
+}
+
+export interface OrgOIDCInput {
+  issuer: string;
+  client_id: string;
+  client_secret: string;
+  enabled: boolean;
+}
+
 class ApiError extends Error {
   constructor(
     public status: number,
@@ -328,7 +396,99 @@ async function request<T>(path: string, options?: RequestInit): Promise<T> {
   return res.json();
 }
 
+/**
+ * Auth endpoints live at the root (not under /api) and report failures as
+ * `{"error": "..."}`, which we surface verbatim so backend validation messages
+ * reach the user.
+ */
+async function authRequest<T>(path: string, options?: RequestInit): Promise<T> {
+  const res = await fetch(path, {
+    credentials: "include",
+    headers: { "Content-Type": "application/json", ...options?.headers },
+    ...options,
+  });
+
+  if (!res.ok) {
+    let message = `HTTP ${res.status}`;
+    try {
+      const body = await res.json();
+      if (body?.error) message = body.error;
+    } catch {
+      // non-JSON body — keep the status message
+    }
+    throw new ApiError(res.status, message);
+  }
+
+  if (res.status === 204) {
+    return undefined as T;
+  }
+
+  return res.json();
+}
+
+export const auth = {
+  bootstrapStatus(): Promise<BootstrapStatus> {
+    return authRequest<BootstrapStatus>("/auth/bootstrap-status");
+  },
+
+  bootstrap(input: { org_name: string; email: string; password: string }): Promise<BootstrapResponse> {
+    return authRequest<BootstrapResponse>("/auth/bootstrap", {
+      method: "POST",
+      body: JSON.stringify(input),
+    });
+  },
+
+  login(email: string, password: string): Promise<{ ok: boolean }> {
+    return authRequest<{ ok: boolean }>("/auth/login", {
+      method: "POST",
+      body: JSON.stringify({ email, password }),
+    });
+  },
+
+  logout(): Promise<void> {
+    return authRequest<void>("/auth/logout", { method: "POST" });
+  },
+
+  me(): Promise<MeResponse> {
+    return authRequest<MeResponse>("/auth/me");
+  },
+
+  /** The URL an admin must register with their OIDC provider. */
+  oidcRedirectUrl(): string {
+    if (typeof window === "undefined") return "/auth/oidc/callback";
+    return `${window.location.origin}/auth/oidc/callback`;
+  },
+};
+
 export const api = {
+  // Organization
+  listOrgUsers(): Promise<OrgUser[]> {
+    return request<OrgUser[]>("/org/users");
+  },
+
+  createOrgUser(input: OrgUserInput): Promise<OrgUser> {
+    return request<OrgUser>("/org/users", { method: "POST", body: JSON.stringify(input) });
+  },
+
+  updateOrgUserRole(userId: string, role: Role): Promise<{ ok: boolean }> {
+    return request<{ ok: boolean }>(`/org/users/${userId}/role`, {
+      method: "PUT",
+      body: JSON.stringify({ role }),
+    });
+  },
+
+  deleteOrgUser(userId: string): Promise<void> {
+    return request<void>(`/org/users/${userId}`, { method: "DELETE" });
+  },
+
+  getOrgOIDC(): Promise<OrgOIDCConfig> {
+    return request<OrgOIDCConfig>("/org/oidc");
+  },
+
+  saveOrgOIDC(input: OrgOIDCInput): Promise<{ saved: boolean }> {
+    return request<{ saved: boolean }>("/org/oidc", { method: "PUT", body: JSON.stringify(input) });
+  },
+
   // Servers
   listServers(): Promise<Server[]> {
     return request<Server[]>("/servers");