docs: create documentation structure
adds minimal, digestible docs that complement the readme:
- architecture.md - system design and data flow
- memory.md - thread context vs episodic memory (key design insight)
- mcp.md - model context protocol integration
- testing.md - testing philosophy and approach
each doc is self-contained, small, and focused. intelligent reader can understand design by reading in aggregate.
also updated readme:
- fixed "thread history (sqlite)" โ "thread context (atproto)"
- added link to docs/ for deeper dive
๐ค Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude <noreply@anthropic.com>