FEAT: add schedule limit validation and improve ES update

- Add cron-validation utility with Airflow presets support (@once, @daily, etc.)
- Validate cron expressions against customer scheduleLimit from DUC
- Fetch scheduleLimit via gRPC to ensure up-to-date configuration
- Improve ES updatePipeline to fetch current doc and merge changes
- Only update fields explicitly provided in PATCH request body
- Preserve config.tables when updating config.cron

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

src/modules/platform-api/platform-api.module.ts

@@ -6,9 +6,10 @@ import { PlatformApiController } from './platform-api.controller';
 import { PlatformApiService } from './platform-api.service';
 import { ElasticsearchModule } from '../../services/elasticsearch';
 import { DynamoDBModule } from '../../services/dynamodb';
+import { CustomersModule } from '../customers/customers.module';
 
 @Module({
-  imports: [ElasticsearchModule, DynamoDBModule],
+  imports: [ElasticsearchModule, DynamoDBModule, CustomersModule],
   controllers: [PlatformApiController],
   providers: [PlatformApiService, DadosferaLogger],
   exports: [PlatformApiService],