Fix RSC toStringTag error: import PrismaClient from generated TS client

Use @/generated/prisma/client instead of @prisma/client to avoid
Turbopack creating a broken external proxy for the missing
.prisma/client/default module at runtime. Add @prisma/adapter-pg
to serverExternalPackages, remove unused resolveAlias.

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

next.config.ts

@@ -3,14 +3,7 @@ import type { NextConfig } from "next";
 const nextConfig: NextConfig = {
   output: "standalone",
   transpilePackages: ["unified", "remark-parse"],
-  serverExternalPackages: ["@prisma/client", "pg"],
-  experimental: {
-    turbo: {
-      resolveAlias: {
-        ".prisma/client/default": "./node_modules/.prisma/client/default.js",
-      },
-    },
-  },
+  serverExternalPackages: ["@prisma/client", "@prisma/adapter-pg", "pg"],
 };
 
 export default nextConfig;