Adds the state-writes spec folder: write plans per write tool (create,
update, delete, document) learned from the first successful recorded call,
the gate that replays the capture's timeline on the initial state and serves
a write tool only when a later read confirms its effect and none contradicts
it, deterministic generated values, the serving contract and what stays
unmodelled.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>