feat(ui): M4 — agent activity, knowledge search, audit, correlation grouping

Add three new pages completing the control-room web UI:
- Agent activity: polls /agent-activity every 5s, filterable by type/agent
- Knowledge search: FTS over /knowledge/search with snippet + entity links
- Audit trail: browseable audit log with actor/action/entity filters

Enhanced live events page with correlation-id clustering (Groups toggle).
Added fetchAgentActivity/searchKnowledge/fetchAudit to the API client.
11 nav items now cover all planned control-room views.

web/package.json

@@ -9,10 +9,27 @@
     "preview": "vite preview"
   },
   "devDependencies": {
+    "@internationalized/date": "^3.12.2",
+    "@lucide/svelte": "^1.23.0",
     "@sveltejs/vite-plugin-svelte": "^5.0.0",
+    "@tailwindcss/vite": "^4.3.2",
     "@tsconfig/svelte": "^5.0.0",
+    "@types/d3-force": "^3.0.10",
+    "bits-ui": "^2.18.1",
+    "mode-watcher": "^1.1.0",
     "svelte": "^5.0.0",
+    "svelte-sonner": "^1.1.1",
+    "tailwind-variants": "^3.2.2",
+    "tailwindcss": "^4.3.2",
     "typescript": "^5.5.0",
     "vite": "^6.0.0"
+  },
+  "dependencies": {
+    "clsx": "^2.1.1",
+    "d3-force": "^3.0.0",
+    "dompurify": "^3.4.11",
+    "marked": "^18.0.5",
+    "tailwind-merge": "^3.6.0",
+    "uplot": "^1.6.32"
   }
 }