feat(frontend): 实现新手引导功能

- 添加 Guide 组件和引导步骤配置
- 实现 useOnboardingTour 和 useTourStepDescription composables
- 添加 onboarding store 管理引导状态
- 更新多个视图和组件以支持引导功能
- 添加国际化支持（中英文）
- 删除旧的实现指南文档

frontend/src/components/layout/AppHeader.vue

@@ -200,6 +200,14 @@
               </div>
 
               <div class="border-t border-gray-100 py-1 dark:border-dark-700">
+                <button @click="handleReplayGuide" class="dropdown-item w-full">
+                  <svg class="h-4 w-4" fill="currentColor" viewBox="0 0 24 24">
+                    <path
+                      d="M12 2a10 10 0 100 20 10 10 0 000-20zm0 14a1 1 0 110 2 1 1 0 010-2zm1.07-7.75c0-.6-.49-1.25-1.32-1.25-.7 0-1.22.4-1.43 1.02a1 1 0 11-1.9-.62A3.41 3.41 0 0111.8 5c2.02 0 3.25 1.4 3.25 2.9 0 2-1.83 2.55-2.43 3.12-.43.4-.47.75-.47 1.23a1 1 0 01-2 0c0-1 .16-1.82 1.1-2.7.69-.64 1.82-1.05 1.82-2.06z"
+                    />
+                  </svg>
+                  {{ $t('onboarding.restartTour') }}
+                </button>
                 <button
                   @click="handleLogout"
                   class="dropdown-item w-full text-red-600 hover:bg-red-50 dark:text-red-400 dark:hover:bg-red-900/20"
@@ -232,7 +240,7 @@
 import { ref, computed, onMounted, onBeforeUnmount } from 'vue'
 import { useRouter, useRoute } from 'vue-router'
 import { useI18n } from 'vue-i18n'
-import { useAppStore, useAuthStore } from '@/stores'
+import { useAppStore, useAuthStore, useOnboardingStore } from '@/stores'
 import LocaleSwitcher from '@/components/common/LocaleSwitcher.vue'
 import SubscriptionProgressMini from '@/components/common/SubscriptionProgressMini.vue'
 
@@ -241,6 +249,7 @@ const route = useRoute()
 const { t } = useI18n()
 const appStore = useAppStore()
 const authStore = useAuthStore()
+const onboardingStore = useOnboardingStore()
 
 const user = computed(() => authStore.user)
 const dropdownOpen = ref(false)
@@ -300,6 +309,11 @@ async function handleLogout() {
   await router.push('/login')
 }
 
+function handleReplayGuide() {
+  closeDropdown()
+  onboardingStore.replay()
+}
+
 function handleClickOutside(event: MouseEvent) {
   if (dropdownRef.value && !dropdownRef.value.contains(event.target as Node)) {
     closeDropdown()