Add src/server/trpc/types.ts for type inference

src/server/trpc/types.ts

@@ -0,0 +1,15 @@
+import type { AppRouter } from './trpc';
+
+/**
+ * Infer procedure output type
+ */
+export type InferProcedureOutput<TRouter, TPath extends keyof TRouter> = 
+  TRouter extends { output: infer TOutput } 
+    ? TOutput extends { [K in TPath]?: infer TProcedure }
+      ? TProcedure extends { output: infer TOutputType }
+        ? TOutputType
+        : never
+      : never
+    : never;
+
+export type { AppRouter };