feat(devx): add the ruled vendor-wire state to check-route-envelope's surface-3 grammar (#10554) (#10562)

Maintainer ruling 2026-08-21 (#10554, option A of the PR #10352 escalation):
surface 3 gains a fourth state, vendorWire, for a body this repo builds whose
shape is a vendor's wire format required by that vendor's client library —
surface 2's kind 3, met as a built literal instead of a relay.

- stays counted like this surface's exempt: closed at exactly N bodies
- note mandatory, labelled vendor: / reader: / partner:
- pairwise exclusive with ratchet and exempt
- widening/adding is ⛔ MAINTAINER-ONLY (#8435 marker discipline)
- the const-hoisting evasion is named in the gate's prose as a forbidden move
- self-test: accept-with-note, reject-without-note, reject beside ratchet and
  exempt, authority marker on widening, shrink direction, empty declaration

Machinery + prose + self-test only: zero entries on main — the adjudicated
entry lands with its file on PR #10352, under the ruling that authorized it.


Claude-Session: https://claude.ai/code/session_01XLSPyJTC8HwTFr1i6hj3rK

Co-authored-by: Claude <noreply@anthropic.com>

Author: os-elon