When merging PR #2105 (Hermes Run Adapter RFC) the standing concern was
that landing the RFC unconfirmed would invite the speculative-fragment
implementation pattern we just had to put on hold with PR #2071 — well-
written 651-LOC standalone scripts with no callers.
Add a single bullet to the conventions block so the contract is explicit:
an RFC is a design direction, not an invitation to PR fragments against
it. Implementation slices need maintainer confirmation first.
Applied during stage-341 build, not requested from @Michaelyklam — the
guardrail belongs in the conventions doc itself rather than as a one-off
ask on this PR.
nesquena-hermes
43677b046d