- Delete 6 legacy RuoYi modules (ruoyi-admin/framework/system/common/quartz/generator)
- Create new iot-platform Spring Boot 2.5.15 module with all IoT business
- Migrate 5 MQTT consumers, VehicleSyncTask, 14 services, 15 domains/mappers
- P0 security fixes:
  - Replace string-concat SQL with field whitelist + escapeValue in TDengineService, DynamicSqlProvider, TDegnineAlarm
  - Externalize hardcoded MQTT/TDengine credentials to application.yml via IotProperties
  - Fix thread-unsafe static shared Connection/Statement in TDegnineAlarm (use per-method connections)
- Logging normalization: replace 148 System.out/err.println with SLF4J, add logback-spring.xml (100MB rolling, 30d retention)
- Dead code cleanup: NumericIdGenerator (238→65 lines), merge TDengineConnecting into TDengineService
- Verified: mvn clean package passes, app boots with all 5 MQTT consumers