openai/gpt-chat-latest → B (5:1)

Side B changes the core ranking behavior from contributor-level to commit-level by comparing every eligible commit, rolling scores back up to contributors, updating prompts, evidence, UI, and adding tests for same-contributor multi-commit cases and new ranking outputs. Side A fixes a real reducer bug by moving the zero-ratio guard before side effects to prevent ghost items and voted pairs, with an accompanying regression test, but its scope is much narrower than the architectural change in Side B.