docs(m177): handoff — §2 is one function short, and the Zig-regression rule is standing

Every piece the lease orchestrator calls now exists; the orchestrator does not.
Records the two SELECTs still missing before it can be written — the
integration-grant reader and the approved-write-gate lookup — and why
`Grants::none()` is a fail-closed placeholder rather than an answer.

Also records: M183_001 rides in this PR and is not stray; the no-Zig-regression
standing instruction with its four confirmed instances and the pin-then-swap
method; and the correction that the prior handoff's "§5 claim-time half ✅"
described a parser with no reader.

Workspace figure measured at this commit rather than carried forward: 820
passed, 0 failed, 81 ignored.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>