gateway: add local backend update action

docs/api/PROTOCOL.md

@@ -384,7 +384,11 @@ Return status for user-level local LLM backend daemons (for example `ollama.serv
 
 #### `system.localBackendControl`
 
-Control a local backend daemon (`start`, `restart`, `stop`).
+Control a local backend daemon (`start`, `restart`, `stop`, `update`).
+
+- `update` semantics:
+  - `ollama`: pulls configured Ollama models (tiers/local providers + embedding/audio models) via `ollama pull`.
+  - `llamacpp`: performs a safe service restart (model file refresh remains external to Flynn).
 
 **Request:**
 ```json

docs/plans/state.json

@@ -3,6 +3,22 @@
   "updated_at": "2026-02-23",
   "description": "Tracks the status of all Flynn plans and implementation phases",
   "plans": {
+    "dashboard-local-backend-update-actions": {
+      "status": "completed",
+      "date": "2026-02-23",
+      "updated": "2026-02-23",
+      "summary": "Extended local backend controls with explicit `update` action support. `ollama` update now pulls configured local models, while `llamacpp` uses a safe restart fallback with clear operator messaging. Updated gateway validation, dashboard action wiring, and regression coverage.",
+      "files_modified": [
+        "src/gateway/handlers/localBackends.ts",
+        "src/gateway/handlers/system.ts",
+        "src/gateway/handlers/handlers.test.ts",
+        "src/gateway/ui/pages/dashboard.js",
+        "src/gateway/ui/pages/dashboard.test.ts",
+        "docs/api/PROTOCOL.md",
+        "docs/plans/state.json"
+      ],
+      "test_status": "pnpm test:run src/gateway/handlers/handlers.test.ts src/gateway/ui/pages/dashboard.test.ts + pnpm typecheck passing"
+    },
     "dashboard-local-backend-daemon-controls": {
       "status": "completed",
       "date": "2026-02-23",