feat(mcp): add Model Context Protocol integration

Add  MCP integration including:
- New MCP settings tab with server configuration
- Tool invocation UI components
- API endpoints for MCP management
- Integration with chat system for tool execution
- Example configurations

app/components/chat/Chat.client.tsx

@@ -28,6 +28,8 @@ import type { ElementInfo } from '~/components/workbench/Inspector';
 import type { TextUIPart, FileUIPart, Attachment } from '@ai-sdk/ui-utils';
 import { useMCPStore } from '~/lib/stores/mcp';
 import type { LlmErrorAlertType } from '~/types/actions';
+import type { TextUIPart, FileUIPart, Attachment } from '@ai-sdk/ui-utils';
+import { useMCPStore } from '~/lib/stores/mcp';
 
 const toastAnimation = cssTransition({
   enter: 'animated fadeInRight',