fix: anvil_pricing 업데이트 시 updated_at 갱신

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/services/sync.ts

@@ -1081,7 +1081,8 @@ export class SyncOrchestrator {
             UPDATE anvil_pricing
             SET
               hourly_price = ?,
-              monthly_price = ?
+              monthly_price = ?,
+              updated_at = CURRENT_TIMESTAMP
             WHERE id = ?
           `).bind(
             hourlyPrice,