Adds audit entries for:
- permission.set (role-level change)
- permission.user_set (per-user override)
- permission.user_reset (clear user override)
- feature.update (global feature flag toggle, per-key with old->new diff)
Old value captured for feature.update for full diff trail.
permissionsController: added audit import, wired audit() after each write.
adminController.updateFeatures: replaced bulk audit with per-key entries
capturing old value from app_settings before overwrite.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Maxim Dolgolyov
539d33df31