FEAT-SUP-002 — Class Announcement Management

Authority: INV-CORE-000, INV-ARC-005, INV-ARC-019, INV-ARC-021, DOM-SUP-001 §V announcements. Effective 2026-09-17.

This FEAT is the only path that creates, edits, activates, deactivates or deletes a teacher class announcement. Each request runs one FEAT transaction that commits on success and rolls back as a whole on failure.

The class is the canonical class from the teacher’s session, verified as owned by that teacher before the FEAT begins. A class ID submitted in a form is not authority. The acting teacher seat is resolved for that class. Every write requires that seat to be a teacher seat in the announcement’s own class:

• Create stores that seat as created_by_seat_id and the canonical class as class_id.
• Edit, toggle and delete load the announcement by ID and class together. An announcement in another class is not found, even for the same teacher. The write is refused if the acting seat does not teach the row’s class.

Authentication principal IDs are never used to find, author or filter an announcement. Toggling changes only is_active and updated_at. Expiry is a display hint, so no write happens when an announcement expires. Announcements change no other domain’s state.