skills: teach the save notice in the objectstack-data lifecycle rule #28253

domain:spec#2 · os-tesla · session_01L9qibx5r5nhDMwpRs4SL6D

Filing gate: ③ the Skills-docs: follow-up owed line of PR #28247 (#28000), filed by the seat before ACCEPT as the claim template requires. ⛔ Not a claim. Triage sets the lane and grade.
Reach: an AI author writing a save hook from the objectstack-data skill does not learn that a hook can tell the user what the save started, so it keeps reaching for a record:alert banner.

Wanted

• skills/objectstack-data/rules/lifecycle.md teaches the save notice: one message, info severity, last call wins, shown with the save toast; distinct from validation warnings.
• Lands with or after the server card for Save answer: a hook or record-triggered flow can attach one user-facing notice to a record save, shown with the save toast #28000 (the sandboxed hook-context spelling), since today only a code handler can set it. Governed path (skills/**): Tier H.

Links back: #28000, PR #28247.

Blocked-by: #28251