Disposition MARS-373 archive-context WARN on 2 immutable applied migrations

Two applied migrations (006-multi-pieza-multi-conducto-schema.sql, 010-2026-06-20-mars153-fn-searchpath-sync.sql) ran DML on an audited table with no SET LOCAL app.user_id/app.archive_reason set, so archivedBy/archiveReason landed NULL for those rows. Applied migrations are immutable per commons — cannot fix in place. MARS-373 archive-context-presence gate WARNs on this at every future push (recurring, permanent, non-actionable-at-source). Disposition needed: acknowledge as known-and-accepted (silence the specific WARN) or leave as a standing recurring alert. Surfaced by coder-mars-cc during MARS-593/wi-cancel push, 2026-07-31, not introduced by that push.