feat: Give API keys their own page and group the sidebar

The token management card sat on /settings, which is owner|admin
throughout, so it hid a capability every member already had: the API has
never required a role to mint or revoke your own key. It is now the
/api-keys page, reachable at every role, with the instance-wide lifetime
cap left behind on /settings because that is policy rather than one
person's credentials — and that split is what lets the page be ungated.

The sidebar gains groups: Fleet, Access, Automation, Instance, each with a
small-caps heading and a rule above it. Grouping is by what the operator
is doing rather than by which service answers, so SSH keys, secrets and
API keys sit together as credentials. A group whose every item is
admin-only disappears whole for a member; a labelled section with nothing
under it reads as a failure rather than a restriction.

The UI says keys while the collection, prefix and routes still say tokens.
Renaming a published endpoint to match a nav label would break every
script already written against it.

CLAUDE.md

@@ -467,6 +467,16 @@ window, answering 429 with `Retry-After`; cookie sessions are untouched; it
 exists so a runaway script cannot take an instance down, not as the general
 API rate-limiting project some future ticket might build.
 
+**The UI calls them API keys and lives at `/api-keys`, not on `/settings`.**
+The page is reachable at **every** role, which is the whole reason it is a page:
+`/settings` is owner|admin throughout, so a card there hid a capability every
+member has. `settings.api_token_max_days` stays on `/settings` because it is
+instance policy rather than one person's credentials, and that split is exactly
+what lets the page be ungated. The label differs from the identifiers on
+purpose — the collection is `api_tokens`, the prefix is `vt_`, the routes are
+`/api/tokens`, and renaming a published endpoint to match a nav label would
+break every script already written against it.
+
 `server/internal/api/docs/openapi.json` is a **generated, committed** OpenAPI
 3.1 document — `swag v2` reading `@…` annotations off the handlers — served at
 `GET /api/openapi.json` and rendered as a reference page by a vendored Scalar
@@ -1012,9 +1022,20 @@ Customer nav is three destinations — Overview, People, Billing. Settings is in
 | `/steps`                                                        | Reusable step library                                                   |
 | `/monitors`, `/monitors/new`, `/monitors/[id][/edit]`           | Checks, uptime, incidents                                               |
 | `/secrets`, `/secrets/[group]`                                  | Vault                                                                   |
+| `/api-keys`                                                     | Personal API keys — reachable at **every** role, unlike `/settings`     |
 | `/audit`                                                        | Audit log                                                               |
 | `/settings`, `/settings/notifications`, `/settings/license`     | Members, OIDC, alerts, retention, ESO token · channels · licence        |
 
+**The sidebar is grouped, and the groups are the nav's structure rather than
+decoration.** `web/components/Sidebar.tsx` holds `navGroups` — Fleet, Access,
+Automation, Instance — each rendered with a mono small-caps heading and a
+hairline rule above it, the first group excepted. Grouping is by what the
+operator is doing, not by which service answers: SSH keys, vault secrets and
+API keys sit together under Access because all three are credentials. A group
+whose every item is `adminOnly` disappears **whole**, heading and rule
+included, for a member — a labelled section with nothing under it reads as
+something that failed to load rather than something withheld.
+
 **`/settings` is one page, not a section.** Members and single sign-on used to
 live at `/settings/instance` with their own sidebar entry; they are now the
 **Access** group at the top of `/settings`, above **Monitoring** and