made tiny updates

packages/app/src/lib/trpc.ts

@@ -0,0 +1,27 @@
+'use client';
+
+// ── tRPC client (Next.js App Router, client components) ───────────────────────
+// Creates a typed tRPC client backed by the TanStack Query context already
+// provided by the app's QueryClientProvider.
+//
+// Usage (in client components):
+//   const summarize = trpc.ai.summarizeDiff.useMutation();
+//   await summarize.mutateAsync({ artboardId, workspaceId, changes });
+
+import { createTRPCReact }  from '@trpc/react-query';
+import { httpBatchLink }    from '@trpc/client';
+import type { AppRouter }   from '@/server/routers/index';
+
+// Typed tRPC hooks — import `trpc` in client components for .useQuery / .useMutation
+export const trpc = createTRPCReact<AppRouter>();
+
+// Raw client for server-side usage (e.g., in Server Actions)
+export function makeTrpcClient() {
+  return trpc.createClient({
+    links: [
+      httpBatchLink({
+        url: '/api/trpc',
+      }),
+    ],
+  });
+}