chore(db): migrate from SQLite to PostgreSQL

- Change Prisma provider from sqlite to postgresql
- Replace better-sqlite3 adapter with @prisma/adapter-pg
- Update prisma.config.ts and lib/prisma.ts for PostgreSQL
- Add DATABASE_URL to .env.local
- Regenerate Prisma client for PostgreSQL
- Recreate migrations for PostgreSQL database

lib/generated/prisma/internal/prismaNamespaceBrowser.ts

@@ -64,6 +64,9 @@ export type ModelName = (typeof ModelName)[keyof typeof ModelName]
  */
 
 export const TransactionIsolationLevel = runtime.makeStrictEnum({
+  ReadUncommitted: 'ReadUncommitted',
+  ReadCommitted: 'ReadCommitted',
+  RepeatableRead: 'RepeatableRead',
   Serializable: 'Serializable'
 } as const)
 
@@ -129,3 +132,11 @@ export const SortOrder = {
 
 export type SortOrder = (typeof SortOrder)[keyof typeof SortOrder]
 
+
+export const QueryMode = {
+  default: 'default',
+  insensitive: 'insensitive'
+} as const
+
+export type QueryMode = (typeof QueryMode)[keyof typeof QueryMode]
+