fix: pass config object directly to PrismaLibSql, drop @libsql/client

PrismaLibSql constructor takes a Config object (with url), not a
pre-created Client instance. Remove the unnecessary createClient call
and the @libsql/client direct dependency.

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

src/lib/prisma.ts

@@ -1,6 +1,5 @@
 import { PrismaClient } from '@prisma/client'
 import { PrismaLibSql } from '@prisma/adapter-libsql'
-import { createClient } from '@libsql/client'
 
 const globalForPrisma = globalThis as unknown as {
   prisma: PrismaClient | undefined
@@ -8,10 +7,9 @@ const globalForPrisma = globalThis as unknown as {
 
 function getPrismaClient(): PrismaClient {
   if (!globalForPrisma.prisma) {
-    const libsql = createClient({
+    const adapter = new PrismaLibSql({
       url: process.env.DATABASE_URL ?? 'file:./dev.db',
     })
-    const adapter = new PrismaLibSql(libsql)
     globalForPrisma.prisma = new PrismaClient({
       adapter,
       log: process.env.NODE_ENV === 'development' ? ['query', 'error', 'warn'] : ['error'],