Look the id up first and authorize only on first sighting; remember refusals within the cap; never re-forward an id whose primary stayed silent; end the connection when an answer cannot be queued; fixed refusal texts; limit_reached cap refusal; commit-point doc on ApplyPut/Delete.
Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
Opt-in per connection by the first hello (or first write); the server answers a
capable hello with its own. A put or delete commits, then gets write_admitted under
its id; every refusal is error.v1 with the id (an unreadable frame carries the id
when it still holds one). (actor, messageId) dedupe is bound to the content hash and
asked only after the write authority grants; same id other content is message_invalid.
The shard write forwarder says hello, waits for the primary's receipt, and the server
relays only what the primary answered under the original id.
Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>