openai/gpt-5.3-chat → A (3:1)

A converts a non-interactive pinned icon into a working unpin control by wiring a POST /ui RPC (including new next_path plumbing) and adds an end-to-end browser test verifying the behavior, delivering real functionality. B only changes row coloring logic from ordinal-based to score-based gradients with unit tests, which is a visual refinement rather than a core capability.