- Add DeptPerm.MANAGE_EQUIPMENT scoped permission constant
- Create migration 0035 for new DepartmentPermission
- Refactor CanManageEquipment permission class with:
* Admin/staff/superuser → full access
* Model permissions → full access (add/change/delete_equipment)
* Department head → own department, can choose responsible
* Scoped permission → own department, responsible forced to head
* Regular members → no access
- Update EquipmentListSerializer with:
* Permission level detection (full/dept_head/scoped/None)
* Auto-fill department and responsible based on permission level
* Validation that responsible is in same department
- Add create_options endpoint returning:
* allowed_departments, can_choose_department, can_choose_responsible
* default_responsible, permission_level
- Add bulk equipment creation support with auto-generated inventory numbers
- Implement 45 comprehensive permission tests (all passing)
- Fix is_active=True in test make_user() fixture
Tests: 45/45 passing ✅
