feat(tutorial): enhance help button visibility and add dialog tests

- Introduced a mechanism to hide the help button when modal dialogs are open by adding `helpButtonHidden` state in the tutorial controller.
- Updated various components to set the help button visibility based on dialog states.
- Added tests to verify help button visibility during reward and task confirmation dialogs.
- Created new E2E tests for dialog help button functionality across different assignment views.
- Refactored existing dialog components to utilize the new help button visibility logic.
- Added unit tests for `RewardConfirmDialog` and `TaskConfirmDialog` to ensure correct titles are rendered based on task type.
- Enhanced `HelpButton` component tests to validate visibility based on tutorial state.

frontend/src/components/child/__tests__/ChildView.spec.ts

@@ -3,6 +3,7 @@ import { mount, VueWrapper } from '@vue/test-utils'
 import { nextTick } from 'vue'
 import ChildView from '../ChildView.vue'
 import { eventBus } from '@/common/eventBus'
+import { helpButtonHidden } from '@/tutorial/controller'
 
 // Mock dependencies
 vi.mock('vue-router', () => ({
@@ -396,6 +397,23 @@ describe('ChildView', () => {
     })
   })
 
+  describe('Help FAB visibility during reward redeem dialog', () => {
+    beforeEach(() => {
+      helpButtonHidden.value = false
+      wrapper = mount(ChildView)
+    })
+
+    it('hides the help button while the reward redeem dialog is open', async () => {
+      wrapper.vm.showRewardDialog = true
+      await nextTick()
+      expect(helpButtonHidden.value).toBe(true)
+
+      wrapper.vm.showRewardDialog = false
+      await nextTick()
+      expect(helpButtonHidden.value).toBe(false)
+    })
+  })
+
   describe('Cancel Pending Reward Dialog', () => {
     const pendingReward = {
       id: 'reward-1',