feat: Keyword-based breakout broadcast targeting

Features:
- !broadcast command now accepts keywords to match groups by name
- !broadcast suas counter fpv broadcasts to groups matching those keywords
- !broadcast all broadcasts to all groups
- Improved breakout announcement tracking with fallback lookups

Changes:
- Track initial breakout announcements in parent group
- Add timestamp range matching (within 5 seconds) for announcements
- Add parent group fallback when timestamp matching fails
- Update help menu and wiki documentation