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

B implements a genuine algorithmic improvement to pair selection (spanning-tree bridging then rank-zip refinement) with clear rationale and thorough new tests validating the logic. A is a large, useful feature (per-room theme cookies + private-room URL prefixing) but is mostly plumbing/threading extra parameters through many call sites, which is real but more mechanical/lower-risk value than B's core-algorithm correctness improvement.