feat: real-time alerts via WebSocket push notifications

- Add ws WebSocket server (port 3001) with JWT auth and user-socket mapping
- Add WebSocket client with exponential backoff reconnection and heartbeat
- Add useRealtimeAlerts hook with toast notifications and unread badge
- Add alert.publisher service (WS → push → email fallback)
- Integrate publisher into DarkWatch, VoicePrint, HomeTitle, SpamShield, RemoveBrokers
- Update Navbar with connection status indicator and unread count
- Add comprehensive tests (14 passing) for server, client, and publisher

pnpm-lock.yaml

@@ -112,6 +112,9 @@ importers:
       vite:
         specifier: ^7.0.0
         version: 7.3.3(@types/node@25.9.1)(jiti@2.7.0)(lightningcss@1.32.0)(terser@5.48.0)(tsx@4.22.3)
+      ws:
+        specifier: ^8.21.0
+        version: 8.21.0
     devDependencies:
       '@types/node-cron':
         specifier: ^3.0.11
@@ -119,6 +122,9 @@ importers:
       '@types/pg':
         specifier: ^8.20.0
         version: 8.20.0
+      '@types/ws':
+        specifier: ^8.18.1
+        version: 8.18.1
       drizzle-kit:
         specifier: ^0.31.10
         version: 0.31.10