~anthropic/claude-sonnet-latest → A (3:2)

Side A fixes a real functional bug (hardcoded staging/production hostnames breaking OAuth/redirect URLs for custom hosts) and DRYs up nearly-identical logic across five auth integration files into one shared `util/get-base-url`, plus corrects the deploy trigger branch — a broad, correctness-critical improvement. Side B fixes a narrower UI/rank-highlighting bug and polishes vote-slider styling with decent added tests, but its impact is confined to one page's visual presentation rather than core app correctness.