system-locked violation types (alpha & terlambat) + proporsional poin alpha per jam

- Migration: add is_system column to violation_types, mark alpha & terlambat
- DestroyType guard: system types cannot be deleted
- UpdateType guard: slug tetap walau nama diubah untuk system types
- UI: delete button hidden, badge lock untuk system types
- Seeder: ViolationTypeDefaultsSeeder untuk fresh deploy
- AttendanceController: lookup by slug (alpha/terlambat) instead of fuzzy match
- Alpha auto-violation: poin proporsional per jam (round((points/10)*count), min 1)
- Terlambat auto-violation: poin fix sesuai jenis (2 poin)
- Also handles both A (alpha) and T (terlambat) statuses for auto-violations

resources/views/components/nav-item.blade.php

@@ -11,6 +11,7 @@ $faIcons = [
     'plus-circle' => 'fa-solid fa-circle-plus',
     'exclamation-triangle' => 'fa-solid fa-triangle-exclamation',
     'users' => 'fa-solid fa-users',
+    'clipboard-check' => 'fa-solid fa-clipboard-check',
     'document-text' => 'fa-solid fa-file-lines',
     'tag' => 'fa-solid fa-tag',
     'list' => 'fa-solid fa-list',
@@ -18,6 +19,7 @@ $faIcons = [
     'refresh' => 'fa-solid fa-rotate',
     'cog' => 'fa-solid fa-gear',
     'users-cog' => 'fa-solid fa-user-gear',
+    'database' => 'fa-solid fa-database',
 ];
 $faClass = $faIcons[$icon] ?? 'fa-solid fa-circle';
 @endphp