~anthropic/claude-sonnet-latest → B (6:4)

Side A is essentially cleanup: deleting a stray duplicate forum.rs so the earlier module split resolves (necessary, but it's dead-code removal/reorg with no new behavior). Side B lands multiple concrete fixes—unpinning via a POST RPC instead of a stale link (real UX/correctness bug), a vote-count tooltip/UI enhancement, matching CSS, and a new unit test plus an updated browser test asserting the corrected unpin behavior—delivering more verifiable, lasting functional value.