- TDengineServiceTest: 14 tests for escapeValue, wrapName, isValidFieldName,
  buildDynamicJson, compressToBase64, insertBatch, close, clearCache
- MqttStatusConsumerTest: 10 tests for topic, clientId, triggermethod,
  handleMessage, null handling, count logic
- MqttFaultConsumerTest: 7 tests for KEY_MAPPING, topic splitting,
  triggermethod trigger/recover types, handleMessage
- VehicleSyncTaskTest: 8 tests for Redis lock, batch exception handling,
  Redis failure, webhook failure, empty data
- JaCoCo check execution with 5% threshold (intermediate target)
- Coverage: 8% → 18% (65 tests total, all passing)