Add tabbed sidebar with MCP server management and resizable interface

- Created tabbed interface with MCP, Conversations, and Inference tabs
- Set MCP tab as default tab
- Added quick connect button for example server with OAuth auth
- Created form to add custom MCP servers with auth type selection
- Implemented server management UI with connect/disconnect/remove actions
- Made sidebar resizable with drag handle (240px-600px range)
- Added comprehensive MCP server status display and tools listing
- Created dedicated Inference tab for OpenRouter connection management

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

src/mcp/connection.ts

@@ -522,6 +522,7 @@ export class MCPConnectionManager {
     try {
       console.log('Initializing MCP client...');
       this.transport = transport;
+      this.transport.onmessage = console.log.bind(console, 'MCP Client message received:');
       this.client = new Client(
         {
           name: 'example-remote-client',