Add end-to-end tests for parent notifications and actions

- Implement tests for approving and denying rewards and chores, including token generation and validation.
- Create tests for error handling scenarios with expired, tampered, and fake tokens.
- Add tests for push subscription registration and user profile notification settings.
- Ensure that notifications reflect the correct state of rewards and chores in the UI.
- Validate that toggles for email digest and push notifications function correctly based on user permissions and server state.

frontend/vue-app/src/components/child/ParentView.vue

@@ -825,6 +825,22 @@ const confirmTriggerReward = async () => {
   }
 }
 
+const denyRewardRequest = async () => {
+  if (!child.value?.id || !selectedReward.value) return
+  try {
+    await fetch(`/api/child/${child.value.id}/deny-reward-request`, {
+      method: 'POST',
+      headers: { 'Content-Type': 'application/json' },
+      body: JSON.stringify({ reward_id: selectedReward.value.id }),
+    })
+  } catch (err) {
+    console.error('Failed to deny reward request:', err)
+  } finally {
+    showRewardConfirm.value = false
+    selectedReward.value = null
+  }
+}
+
 function goToAssignTasks() {
   if (child.value?.id) {
     router.push({
@@ -1168,6 +1184,7 @@ function goToAssignRewards() {
       :reward="selectedReward"
       :childName="child?.name"
       @confirm="confirmTriggerReward"
+      @deny="denyRewardRequest"
       @cancel="
         () => {
           showRewardConfirm = false

frontend/vue-app/src/components/child/RewardConfirmDialog.vue

@@ -12,6 +12,7 @@
     </div>
     <div class="modal-actions">
       <button @click="$emit('confirm')" class="btn btn-primary">Yes</button>
+      <button v-if="reward?.redeeming" @click="$emit('deny')" class="btn btn-danger">Deny</button>
       <button @click="$emit('cancel')" class="btn btn-secondary">Cancel</button>
     </div>
   </ModalDialog>
@@ -28,6 +29,7 @@ defineProps<{
 
 defineEmits<{
   confirm: []
+  deny: []
   cancel: []
 }>()
 </script>