advance_submissions.advance_section_id FK changed from cascadeOnDelete
to nullOnDelete; column made nullable. Aligns implementation with
RFC v0.2 §5.4 audit-immutability ("submissions remain for retention
compliance") — when ArtistEngagementObserver::deleted hard-deletes a
section, its submissions persist as orphans rather than disappearing.
Migration edited in place (branch unpushed, dev-only). Observer
docblock + test assertion updated to match. Removed pre-existing
follow-up comment that documented the deviation.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
ArtistEngagementObserver:
- creating: auto-fills organisation_id from parent Artist (RFC v0.2 D10
denormalisation), asserts artist.organisation_id == event.organisation_id;
cross-tenant linkage throws CrossTenantEngagementException (extends
DomainException, included in this commit).
- saving: no-op marker reserved for Session 2 state-machine validation.
- deleted: cascades soft-delete to Performance children, hard-deletes
AdvanceSection children. AdvanceSubmission rows are immutable per
RFC §5.4 and remain attached.
PerformanceObserver:
- saving: increments version by 1 on UPDATE only (D14 optimistic lock).
MoveTimetablePerformanceRequest in Session 2 uses this for concurrent-
edit detection.
Both observers registered in AppServiceProvider::boot.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
