feat: add MCP server testing and tool listing functionality

- Add MCPTestService for testing MCP server connections
- Support stdio, SSE, and HTTP transport types
- Implement workaround for SSE headers bug (SDK Issue #436)
- Create API routes for /api/mcp/test and /api/mcp/tools
- Add API client methods for MCP operations
- Create MCPToolsList component with collapsible schema display
- Add Test button to MCP servers section with status indicators
- Add Headers field for HTTP/SSE servers
- Add Environment Variables field for stdio servers
- Fix text overflow in tools list display

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

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

libs/types/src/settings.ts

@@ -173,6 +173,8 @@ export interface MCPToolInfo {
   name: string;
   /** Description of what the tool does */
   description?: string;
+  /** JSON Schema for the tool's input parameters */
+  inputSchema?: Record<string, unknown>;
   /** Whether this tool is enabled for use (defaults to true) */
   enabled: boolean;
 }