Unit-tier rebuild of drift-trio S4/S4b (findings A-4): two bound editors over
a held Y relay, conflicts released in fixed order, asserting Y.Doc convergence
FIRST then native projections against the doc. Pinned clientIDs make the LWW
winner deterministic; reverse-order release must converge byte-identically.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01UZJ1pUePb4W47hGoLMYTw4