Add comprehensive architecture design for thicket CLI
- Modern Python stack: Typer + Rich + GitPython + feedparser + pydantic
- Feed auto-discovery: extracts user metadata from Atom/RSS feeds
- Duplicate management: manual curation via duplicates.json
- Git store: single branch, permanent history, sanitized filenames
- Cron-friendly: designed for scheduled execution
- Complete data models and CLI command structure
🤖 Generated with [Claude Code](https://claude.ai/code)
Co-Authored-By: Claude <noreply@anthropic.com>