Feature: tinyTikTok 控制层

**Is your feature request related to a problem? Please describe.**
负责对接客户端等第三方的服务

**Describe the solution you'd like**
- [x] comment
- [x] favorite
- [x] feed
- [x] publish
- [x] user

**Describe alternatives you've considered**
A clear and concise description of any alternative solutions or features you've considered.

**Additional context**
Add any other context or screenshots about the feature request here.

No files, tests, or entry points are mentioned. Start by mapping the existing Go project structure and client-facing service boundaries, then clarify the intended control layer for comment, favorite, feed, publish, and user integrations; done criteria are not defined beyond covering those areas.

Written by the indexing model from the issue text.