Implement account deletion handling and improve user feedback

- Added checks for accounts marked for deletion in signup, verification, and password reset processes.
- Updated reward and task listing to sort user-created items first.
- Enhanced user API to clear verification and reset tokens when marking accounts for deletion.
- Introduced tests for marked accounts to ensure proper handling in various scenarios.
- Updated profile and reward edit components to reflect changes in validation and data handling.

frontend/vue-app/src/components/reward/RewardEditView.vue

@@ -36,7 +36,7 @@ const fields: {
 }[] = [
   { name: 'name', label: 'Reward Name', type: 'text', required: true, maxlength: 64 },
   { name: 'description', label: 'Description', type: 'text', maxlength: 128 },
-  { name: 'cost', label: 'Cost', type: 'number', required: true, min: 1, max: 1000 },
+  { name: 'cost', label: 'Cost', type: 'number', required: true, min: 1, max: 10000 },
   { name: 'image_id', label: 'Image', type: 'image', imageType: 2 },
 ]
 // removed duplicate defineProps