docs: complete developer documentation (5 guides + index)
- 01-快速开始: local setup for all 3 modules, common issues - 02-配置说明: all env vars, WeChat/Pay/DB/COS config details - 03-架构说明: system overview, directory structure, data flows - 04-部署指南: Tencent Cloud SCF/COS deployment, launch checklist - 05-API接口文档: all 42 endpoints with params and response format - README index with audience guide and quick links
这个提交包含在：
Guoguo