feat(maf): conversation-driven MAF roundtable (R1/R2) + server-owned stage-3 dispatch

Backend:
- Conversation API at /api/maf-roundtable/conversations: create/list/detail,
  paginated messages, atomic send+run start, owner-only isolation,
  admin read-only diagnostic access
- SSE real-time event stream (GET /conversations/{id}/stream) backed by
  ConversationEventHub + conversation_events store; multi-worker deployment doc
- Deterministic server-owned stage-3 dispatch contracts (dispatch_contracts.py):
  routing resolved from trusted MAF deployment config instead of manager-chosen
  agent ids; config.yaml keeps stage-3 routing deployment-owned
  (default_manager_agent_id / seat ids / business_routes / max_seats_per_run)
- Conversation persistence (conversations/messages stores) + v2 migration script
- Tests: conversations, conversation stream, migration, phase3 conversation dispatch

Frontend:
- Vitest test infra for MAF (vitest.maf.config.ts + test:maf script) with
  component tests for ApprovalCard/RunHeader/SessionsPage and use-maf-events
- Session form lib, flow-graph dialog / run-detail / sessions page updates,
  routes and nav tweaks
- Docs: R0 legacy interaction baseline mapping, updated implementation plan

Co-authored-by: Cursor <cursoragent@cursor.com>

frontend-web/package.json

@@ -11,6 +11,7 @@
     "build:network": "node --max-old-space-size=8192 ./node_modules/vite/bin/vite.js build --mode network",
     "preview": "vite preview",
     "typecheck": "tsc --noEmit",
+    "test:maf": "vitest run --config vitest.maf.config.ts",
     "check:chrome109-css": "node scripts/check-chrome109-css.mjs",
     "check:legacy-chrome-css": "node scripts/check-chrome109-css.mjs"
   },
@@ -106,19 +107,23 @@
   },
   "devDependencies": {
     "@tailwindcss/postcss": "^4.0.15",
+    "@testing-library/react": "^16.3.2",
+    "@testing-library/user-event": "^14.6.1",
     "@types/file-saver": "^2.0.7",
     "@types/gsap": "^3.0.0",
     "@types/node": "^20.14.10",
     "@types/react": "^19.0.0",
     "@types/react-dom": "^19.0.0",
     "@vitejs/plugin-react": "^5.0.4",
+    "jsdom": "^30.0.1",
     "lightningcss": "^1.30.2",
     "postcss": "^8.5.3",
     "tailwindcss": "^4.0.15",
     "tw-animate-css": "^1.4.0",
     "typescript": "^5.8.2",
     "vite": "^6.0.0",
-    "vite-plugin-source-identifier": "^1.1.2"
+    "vite-plugin-source-identifier": "^1.1.2",
+    "vitest": "^4.1.10"
   },
   "packageManager": "pnpm@10.26.2"
 }