Add a visual histogram showing branch age distribution to help users understand their repository's branch hygiene at a glance. ## Acceptance Criteria - [ ] Add --histogram flag to branches command - [ ] Display age buckets (0-7d, 7-30d, 30-90d, 90d+) - [ ] Use color coding (green/yellow/red) for age ranges - [ ] Show branch count per bucket
Add a visual histogram showing branch age distribution to help users understand their repository's branch hygiene at a glance.
Acceptance Criteria