Services are referenced by appointments, sessions, invoices and payment history,
so deleting one orphans/corrupts those records (deleting a section cascaded to
its services too). Make deletion impossible:
- Backend: DELETE /service-item/{uuid} and DELETE /service-section/{uuid} now
always return 409 (ERR_SERVICE_ITEM_IN_USE) with a message pointing to
deactivate; no rows are touched. Deactivate stays via PATCH active=false.
- Frontend: removed the section delete button, its confirm dialog, the delete
mutation, and the now-unused delete state/flag/icon from ClinicServicesPage.
Section and item deactivate toggles are unchanged.
Tests: ServiceItemDeleteCleanupTest rewritten — delete of item and section both
rejected (409) and the row survives. docs/api/clinic-services.md updated.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>