perf(server): background branch lookups share one GitHub query per sweep (#16760)

Co-authored-by: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
c93080b0a3Theo Browne committed on 10/7/2026, 8:32:35 AM· committed by GitHubparent10395bc
2 files changedLine totals unavailable