Adds department_type column (idara/qism) to hr_departments. Idaras are
top-level administrations; aqsam (sections) belong to an idara via
parent_id. Employees are assigned to a qism.

Cascading changes across 14 files:
- Migration adds department_type with CHECK constraint
- Model: allIdaras(), allAqsam(), getAqsamByIdara() helpers
- Controller: type-aware CRUD, validation (qism requires parent)
- Views: cascading إدارة→قسم dropdowns in employee form, type badges
  in department list, grouped optgroups in employee filters
- Reports: headcount groups by idara
- Routes: new /hr/departments/{id}/aqsam-json endpoint
- Bootstrap: updated Arabic labels
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>