feat: Implement Worker Service with session management and SDK integration

- Added WorkerService to handle long-running HTTP service with session management.
- Implemented endpoints for initializing, observing, finalizing, checking status, and deleting sessions.
- Integrated with Claude SDK for processing observations and generating responses.
- Added port allocator utility to dynamically find available ports for the service.
- Configured TypeScript settings for the project.

.claude-plugin/marketplace.json

@@ -6,7 +6,7 @@
   "plugins": [
     {
       "name": "claude-mem",
-      "source": "./claude-mem",
+      "source": "./plugin",
       "description": "Persistent memory system for Claude Code"
     }
   ]