feat: Implement Worker Service for long-running HTTP service with PM2 management

- Introduced WorkerService class to handle HTTP requests and manage sessions.
- Added endpoints for health check, session management, and data retrieval.
- Integrated ChromaSync for background data synchronization.
- Implemented SSE for real-time updates to connected clients.
- Added error handling and logging throughout the service.
- Cached Claude executable path for improved performance.
- Included settings management for user configuration.
- Established database interactions for session and observation management.

src/services/worker/DatabaseManager.ts

@@ -81,13 +81,9 @@ export class DatabaseManager {
     return this.chromaSync;
   }
 
-  /**
-   * Cleanup orphaned sessions from previous runs
-   * @returns Number of sessions cleaned
-   */
-  cleanupOrphanedSessions(): number {
-    return this.getSessionStore().cleanupOrphanedSessions();
-  }
+  // REMOVED: cleanupOrphanedSessions - violates "EVERYTHING SHOULD SAVE ALWAYS"
+  // Worker restarts don't make sessions orphaned. Sessions are managed by hooks
+  // and exist independently of worker state.
 
   /**
    * Get session by ID (throws if not found)