fix(conversation): enable auto-migration on app startup

- Add migrations path to TypeORM config
- Set migrationsRun: true to run pending migrations on startup
- This ensures V2 columns are created automatically when app starts

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

packages/services/conversation-service/src/app.module.ts

@@ -25,6 +25,8 @@ import { HealthModule } from './health/health.module';
         password: configService.get('POSTGRES_PASSWORD'),
         database: configService.get('POSTGRES_DB', 'iconsulting'),
         entities: [__dirname + '/**/*.entity{.ts,.js}'],
+        migrations: [__dirname + '/migrations/*{.ts,.js}'],
+        migrationsRun: true, // 自动运行迁移
         synchronize: configService.get('NODE_ENV') === 'development',
         logging: configService.get('NODE_ENV') === 'development',
       }),