feat: add support for Drizzle's $onUpdate functionality with @updatedAt

[Balance8]

🚀 Feature: Support for Drizzle's new $onUpdate functionality

This PR adds support for Drizzle ORM v0.30.5's new $onUpdate functionality by mapping Prisma's @updatedAt attribute to Drizzle's $onUpdate(() => new Date()).

📋 Changes

• PostgreSQL Generator: Maps @updatedAt to .$onUpdate(() => new Date())
• MySQL Generator: Maps @updatedAt to .$onUpdate(() => new Date())
• SQLite Generator: Maps @updatedAt to .$onUpdate(() => new Date())

🎯 Implementation Details

• Follows established codebase patterns for field modifier handling
• Consistent implementation across all three database generators
• Uses Prisma's native field.isUpdatedAt DMMF property
• Zero breaking changes to existing functionality
• Minimal code changes (3 lines per generator)

📖 Usage

Prisma Schema:

model User {
  id        Int      @id @default(autoincrement())
  name      String
  createdAt DateTime @default(now())
  updatedAt DateTime @updatedAt  // This will now use $onUpdate
}

Generated Drizzle Schema:

export const User = pgTable('User', {
  id: serial('id').primaryKey(),
  name: text('name').notNull(),
  createdAt: timestamp('createdAt', { precision: 3 }).notNull().defaultNow(),
  updatedAt: timestamp('updatedAt', { precision: 3 }).notNull().$onUpdate(() => new Date())
});

🔗 Related

• Drizzle ORM v0.30.5 release: https://orm.drizzle.team/docs/latest-releases/drizzle-orm-v0305
• Drizzle $onUpdate documentation: https://orm.drizzle.team/docs/column-types/pg

✅ Testing

• All existing tests pass
• Build completes successfully
• Follows TypeScript strict mode requirements

This enhancement provides seamless integration between Prisma's @updatedAt attribute and Drizzle's new $onUpdate functionality, enabling automatic timestamp updates when records are modified.