Jengro777

Add a new business module to RuoQi-v following Clean Architecture. Use when asked to add a new CRUD API, business domain entity, route group, or data table. Covers schema struct, DTO, domain validation, usecase, handler, and route registration in V with veb + V ORM.

RuoQi-v 项目命名规范：SaaS 多租户的 product/subproduct、app/subapp、portal/subportal 三层订阅模型，以及 pf_/tn_ 表前缀、外键命名规则。涉及命名、表设计、字段命名时参考。