docs: document the workload registry

CLAUDE.md

@@ -360,6 +360,76 @@ Two environment variables: `VANTAGE_TRIVY_DB_REF` mirrors the artifact for
 air-gapped installs, and `VANTAGE_VULNDB_DISABLED` switches the puller and
 scheduler off entirely.
 
+### Workload registry
+
+A **workload** is one Docker container or one systemd unit — one word for the
+page, the collection and the commands, rather than saying "container or
+service" in every identifier. Linux only, and **not gated by licence**: this
+reads as core fleet management, so v1 ships everywhere with no `HasFeature`
+check. If that changes the check belongs at `ReportWorkloads`, gating collection
+rather than display, exactly as sub-project A does.
+
+Agents collect on a 60-second ticker and report through `ReportWorkloads` with
+the **offer-then-send** handshake the package report already uses. The offer is
+identified by an explicit `full` flag, **not by an empty workloads list**: a
+host genuinely running nothing sends an empty list as its full report, and
+inferring the offer from emptiness leaves that host answering `need_full` every
+60 seconds forever and never storing anything.
+
+**The on-demand refresh returns no data.** `RefreshWorkloadsCmd` carries nothing
+back; it makes the agent report through the normal RPC and the UI refetches. A
+refresh that returned workloads inline would be a second writer for
+`server_workloads`, arriving by a different route with its own serialisation and
+its own opportunity to disagree with the periodic one. One writer, one shape.
+Opening the panel dispatches a refresh because the panel has a Restart button on
+it, and a stale row is a wrong action aimed at a container that already died.
+
+Two operations do answer back, both over the bus, both with `Await` called
+**before** dispatch: control actions reuse the existing `CommandResult`, and log
+reads get `WorkloadLogsResult`. `CommandStream` republishes **every**
+`CommandResult` onto `bus.ResultChannel` — publishing with no subscriber is a
+no-op, so this costs nothing and avoids a second result path.
+
+**The protected set is computed agent-side and enforced agent-side.**
+`vantage-agent.service`, plus the container ID read from `/proc/self/cgroup`
+should the agent ever run in a container. As with the console relay hardcoding
+`127.0.0.1`, the control plane may name a target but the agent decides what it
+will do to itself; a server-side denylist alone would be bypassed by the next
+dispatch path someone adds, and the failure is unrecoverable from the UI. The
+reported `Protected` flag is the courtesy that greys the button; the agent's own
+check is the boundary. The API answers **409** when it fires — nothing failed.
+
+Collection avoids parsing English: `docker ps -aq` then
+`docker inspect --format '{{json .}}'`, because `docker ps` reports health and
+uptime inside a human `Status` string that is localised and reworded between
+releases. Compose stacks come from the `com.docker.compose.project` label, never
+from YAML on disk — a compose file there may not be what is running. systemd
+uses **column** output, not `--output=json`, which needs systemd 246+.
+
+`DockerOK`/`DockerError` are two fields because there are three states: not
+installed (common on this fleet, and not a fault), installed but not responding,
+and running nothing. The UI must render the first as "not in use here" rather
+than an empty list.
+
+Logs are capped at **500 lines and 256KB, whichever binds first** — a line count
+alone does not bound size, and 500 lines of 4KB JSON is 2MB across the bus. The
+cap is mirrored in `services.MaxWorkloadLogLines` because `agent/` is a separate
+module with an `internal/` tree and the constant cannot be shared; change one,
+change the other. There is **no follow mode**: the browser console already gives
+a real terminal where `docker logs -f` works properly. Log reads and control
+actions are **owner|admin and audited**, unlike the read-only snapshot — a
+container's stdout is arbitrary and cannot be masked the way a workflow's can.
+
+`server_workloads` is one document per server, mirroring `server_packages`, and
+is in `ScopedCollections` (which `scopedCollectionsForPurge` derives from). There
+is no history: a workload list is state, not a record.
+
+**`proto/vantage/v1/vantage.proto` is documentation, not a generator input.**
+Both `pb` packages are hand-written JSON-tagged structs over a custom codec, and
+there are two copies — `agent/internal/grpc/pb` and `server/internal/grpc/pb`.
+A message added to one must be added to the other and to the `.proto`, in the
+same commit.
+
 ### Agent self-update
 
 `UpdateAgentCmd` carries a target version and Gitea base URL; the agent downloads and replaces itself.
@@ -512,6 +582,7 @@ service Vantage {
   rpc SyncKeys(SyncRequest)                  returns (SyncResponse);
   rpc UploadGeneratedKey(UploadKeyRequest)   returns (UploadKeyResponse);
   rpc ReportUpdates(ReportUpdatesRequest)    returns (ReportUpdatesResponse);
+  rpc ReportWorkloads(ReportWorkloadsRequest) returns (ReportWorkloadsResponse);
   rpc ReportInventory(InventoryReport)       returns (InventoryReportResponse);
   rpc SyncMonitors(SyncMonitorsRequest)      returns (SyncMonitorsResponse);
   rpc ReportChecks(ReportChecksRequest)      returns (ReportChecksResponse);
@@ -521,7 +592,8 @@ service Vantage {
 
 `CommandStream` is the only streaming RPC: the agent authenticates once with `AgentReady`, then the server pushes `ServerCommand`s and the agent replies with `CommandResult`, `StepResult`, or `StepOutputChunk`.
 
-`ServerCommand` variants: `GenerateKeyCmd`, `DeleteKeyCmd`, `UpdateAgentCmd`, `ApplyUpdatesCmd`, `RunStepCmd`, `CleanupWorkspaceCmd`, `OpenProxyCmd`, `PingCmd`.
+`ServerCommand` variants: `GenerateKeyCmd`, `DeleteKeyCmd`, `UpdateAgentCmd`, `ApplyUpdatesCmd`, `RunStepCmd`, `CleanupWorkspaceCmd`, `OpenProxyCmd`, `PingCmd`, `RefreshWorkloadsCmd`, `ControlWorkloadCmd`,
+`WorkloadLogsCmd`.
 
 **`PingCmd` is a liveness beat, and it is not redundant with gRPC keepalive.**
 The server sends one every 20s on an otherwise idle command stream; the agent
@@ -578,6 +650,10 @@ vulns        GET /vulnerabilities · GET /vulnerabilities/summary
              GET /servers/:id/vulnerabilities · GET /servers/:id/packages
              GET /packages/search?name=
              GET,POST /vuln-rules · PUT,DELETE /vuln-rules/:id     (owner|admin)
+workloads    GET /workloads · GET /servers/:id/workloads
+             POST /servers/:id/workloads/refresh
+             POST /servers/:id/workloads/:wid/action        (owner|admin)
+             GET /servers/:id/workloads/:wid/logs           (owner|admin)
 audit        GET /audit
 agent        GET /agent/latest-version
 settings     GET,PUT /settings · POST /settings/secrets-token       (owner|admin)
@@ -658,7 +734,7 @@ Paddle is merchant of record; `admin/internal/paddle` is a thin REST client (no
 
 ## MongoDB Collections
 
-`servers` · `keys` · `assignments` · `orgs` · `users` · `auth_providers` · `settings` · `secrets` · `workflows` · `workflow_steps` · `workflow_runs` · `workflow_log_lines` · `workflow_log_seq` · `monitors` · `incidents` · `monitor_rollups` · `notification_channels` · `console_sessions` · `audit_logs` · `server_packages` · `vuln_findings` · `vuln_alert_rules` · `vulndb_meta` · `migrations`
+`servers` · `keys` · `assignments` · `orgs` · `users` · `auth_providers` · `settings` · `secrets` · `workflows` · `workflow_steps` · `workflow_runs` · `workflow_log_lines` · `workflow_log_seq` · `monitors` · `incidents` · `monitor_rollups` · `notification_channels` · `console_sessions` · `audit_logs` · `server_packages` · `vuln_findings` · `vuln_alert_rules` · `vulndb_meta` · `server_workloads` · `migrations`
 
 Every document except `migrations` carries `org_id`. Struct definitions are the source of truth — see `server/internal/models/`.