docs: correcties CLAUDE.md en prisma-client patroon

- Next.js versie gecorrigeerd naar 16 in CLAUDE.md
- prisma-client.md bijgewerkt met werkelijke adapter-implementatie (SQLite + PostgreSQL)

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

docs/patterns/prisma-client.md

@@ -2,14 +2,37 @@
 
 ## lib/prisma.ts
 
+Detecteert automatisch SQLite (lokaal, `file:`) of PostgreSQL (Neon/Vercel).
+
 ```ts
 import { PrismaClient } from '@prisma/client'
+import { PrismaBetterSqlite3 } from '@prisma/adapter-better-sqlite3'
+import { Pool } from 'pg'
+import { PrismaPg } from '@prisma/adapter-pg'
+
+function createPrismaClient() {
+  const url = process.env.DATABASE_URL
+  if (!url) throw new Error('DATABASE_URL is not set')
+
+  if (url.startsWith('file:')) {
+    const adapter = new PrismaBetterSqlite3({ url })
+    return new PrismaClient({
+      adapter,
+      log: process.env.NODE_ENV === 'development' ? ['error', 'warn'] : ['error'],
+    })
+  }
+
+  const pool = new Pool({ connectionString: url })
+  const adapter = new PrismaPg(pool)
+  return new PrismaClient({
+    adapter,
+    log: process.env.NODE_ENV === 'development' ? ['error', 'warn'] : ['error'],
+  })
+}
 
 const globalForPrisma = globalThis as unknown as { prisma: PrismaClient | undefined }
 
-export const prisma = globalForPrisma.prisma ?? new PrismaClient({
-  log: process.env.NODE_ENV === 'development' ? ['query', 'error', 'warn'] : ['error'],
-})
+export const prisma = globalForPrisma.prisma ?? createPrismaClient()
 
 if (process.env.NODE_ENV !== 'production') globalForPrisma.prisma = prisma
 ```