~anthropic/claude-sonnet-latest → B (3:1)

Side B is a substantial feature commit: it adds real post-vote preview morphing, sorted edge-history rendering, a new fullscreen layout mode with CSS across three themes, updated tests/assertions, and documentation—concrete lasting functionality. Side A is a small, useful config simplification (kaocha auto-discovery) but is much narrower in scope and impact than B's multi-file feature work.