feat: add automation, reminders, notifications, msg search, session export, image analysis, host exec, PWA, Docker, E2E, CI/CD

- Automation: rules CRUD (in-memory store + API)
- Reminders: CRUD (in-memory store + API)
- Notifications: push interface for future push server
- Message search: API endpoint with DB-backed query
- Session export: /sessions/:id/export → Markdown
- Image analysis: API stub for multimodal LLM
- Host exec: API stub for Docker sandbox
- PWA: manifest.json + service worker
- Docker: Dockerfile + docker-compose.yml
- E2E: Playwright test scaffold
- CI/CD: GitHub Actions workflow (go test + tsc)

frontend/web/src/main.tsx

@@ -5,6 +5,11 @@ import App from './App'
 import './index.css'
 import './store/themeStore' // Initialize theme (light mode default, follows system)
 
+// Register PWA service worker
+if ('serviceWorker' in navigator) {
+  navigator.serviceWorker.register('/sw.js')
+}
+
 createRoot(document.getElementById('root')!).render(
   <StrictMode>
     <BrowserRouter>