feat: add Core OSS

- https://github.com/yamadashy/repomix - 📦 Repomix is a powerful tool that packs your entire repository into a single, AI-friendly file. Perfect for when you need to feed your codebase to Large Language Models (LLMs)
```
npx repomix@latest && repomix
```

- https://github.com/hardikpandya/stop-slop - For removing AI tells from prose and https://github.com/op7418/humanizer-zh - Humanizer