feat: 完善视频学习进度缓存

完善新手导航和三大创作模块的视频完成缓存、未完成提示与学习进度计算，确保进度按实际学习资源完成情况更新。

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/views/interview/work/index.vue

@@ -21,7 +21,10 @@ const interview = useInterviewStore()
 
 type WorkTab = 'vlog' | 'case' | 'profession' | 'idea'
 
-const selected = ref<WorkTab>('case')
+const selected = computed({
+  get: () => interview.workSelectedTab as WorkTab,
+  set: (value: WorkTab) => interview.setWorkSelectedTab(value),
+})
 const workSideSwitcherRef = ref<InstanceType<typeof WorkSideSwitcher>>()
 
 const isGuideInterviewTask = computed(() => interview.isGuideInterviewTask)