fix(mcp): pass the GUI's AppHandle as Some(..) to the handler (T10.4)

Follows the previous commit's WaMcpHandler::new signature change.

src-tauri/src/mcp/server.rs

@@ -63,7 +63,7 @@ impl McpServer for RmcpServer {
                 let local_addr = listener
                     .local_addr()
                     .map_err(|e| McpError::Server(e.to_string()))?;
-                let handler = WaMcpHandler::new(self.store.clone(), self.app.clone());
+                let handler = WaMcpHandler::new(self.store.clone(), Some(self.app.clone()));
                 let handle = http_transport::serve(listener, auth_token.clone(), handler);
                 let endpoint = format!("http://{local_addr}/mcp");
                 *self.running.lock().await = Some(Running::Http(handle));