Fix Prisma 7 import: use /client suffix

Prisma 7 no longer generates index.ts — entry point is client.ts.
Import changed from @/generated/prisma to @/generated/prisma/client.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/lib/prisma.ts

@@ -1,4 +1,4 @@
-import { PrismaClient } from "@/generated/prisma";
+import { PrismaClient } from "@/generated/prisma/client";
 
 const globalForPrisma = globalThis as unknown as {
   prisma: PrismaClient | undefined;