Replace monopam changelog generation with Claude-powered narratives
- Add Changelog module for Claude-based changelog generation
- Generate narrative prose (2-4 sentences) instead of bullet points
- Auto-detect channel members and use @**Name** Zulip mentions
- Focus on user-visible features and API changes
- Remove monopam dependency from poe library
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>