feat: granular permissions, export backup, user/role management

- PermissionSeeder: 29 permissions with role mapping (admin/manager/staff)
- Policies updated to use hasPermissionTo() instead of hasRole()
- ExportBackup command: JSON per-table backup with chunk processing
- UserResource: CRUD users with role assignment (admin only)
- RoleResource: CRUD roles with permission assignment (admin only)
- UserPolicy + RolePolicy: admin-only access control
- ImportCskh: detailed skip logging with color in dry-run mode
- Widgets: permission-based visibility checks
- Tests: 8/8 pass (21 assertions)

app/Policies/ProductPolicy.php

@@ -9,27 +9,27 @@ class ProductPolicy
 {
     public function viewAny(User $user): bool
     {
-        return $user->hasRole(['admin', 'manager', 'staff']);
+        return $user->hasPermissionTo('view-product');
     }
 
     public function view(User $user, Product $product): bool
     {
-        return $user->hasRole(['admin', 'manager', 'staff']);
+        return $user->hasPermissionTo('view-product');
     }
 
     public function create(User $user): bool
     {
-        return $user->hasRole(['admin', 'manager']);
+        return $user->hasPermissionTo('create-product');
     }
 
     public function update(User $user, Product $product): bool
     {
-        return $user->hasRole(['admin', 'manager']);
+        return $user->hasPermissionTo('update-product');
     }
 
     public function delete(User $user, Product $product): bool
     {
-        return $user->hasRole('admin');
+        return $user->hasPermissionTo('delete-product');
     }
 
     public function restore(User $user, Product $product): bool