feat: WeChat Pay integration, translation quota management, login UX fixes

- WeChat Pay APIv3 integration (JSAPI + Native) with cert-based auth
- TranslationQuota model + admin management UI (配额 tab)
- Alibaba MT provider now checks quota before translation
- Fix: admin tabs scrollable on mobile, remove header-card
- Fix: profile/login navigation - logout stays on profile, login returns to profile
- Fix: login form now visible by default (no extra click to show)
- Fix: home page translate link uses navigateTo (was switchTab to non-tabBar page)
- Add .coverage and apiclient_key.pem to gitignore

uni-app/src/pages/profile/profile.vue

@@ -103,6 +103,7 @@
 
 <script setup>
 import { ref, computed, onMounted } from 'vue'
+import { onShow } from '@dcloudio/uni-app'
 import { authApi } from '@/utils/api.js'
 import AiAssistant from '@/components/ai-assistant.vue'
 import { STORAGE_KEYS, PAGES, TIER_LABELS } from '@/config.js'
@@ -121,11 +122,18 @@ const initials = computed(() => {
 const tierLabel = computed(() => TIER_LABELS[user.value.tier] || '免费版')
 
 const loadUser = async () => {
+  const token = uni.getStorageSync(STORAGE_KEYS.TOKEN)
+  if (!token) {
+    user.value = { tier: 'guest' }
+    return
+  }
   try {
     const res = await authApi.getUserInfo()
     user.value = res
     editForm.value = { username: res.username || '', email: res.email || '' }
-  } catch {}
+  } catch {
+    user.value = { tier: 'guest' }
+  }
 }
 
 const saveProfile = async () => {
@@ -162,7 +170,7 @@ const changePwd = async () => {
   }
 }
 
-const goLogin = () => uni.reLaunch({ url: PAGES.LOGIN })
+const goLogin = () => uni.navigateTo({ url: PAGES.LOGIN })
 const goUpgrade = () => uni.navigateTo({ url: PAGES.UPGRADE })
 const goFeedback = () => uni.navigateTo({ url: PAGES.FEEDBACK })
 const goAgreement = (type) => uni.navigateTo({ url: `/pages/agreement/${type}` })
@@ -175,13 +183,14 @@ const logout = () => {
       if (res.confirm) {
         uni.removeStorageSync(STORAGE_KEYS.TOKEN)
         uni.removeStorageSync(STORAGE_KEYS.REFRESH_TOKEN)
-        uni.reLaunch({ url: PAGES.LOGIN })
+        user.value = { tier: 'guest' }
       }
     },
   })
 }
 
 onMounted(loadUser)
+onShow(loadUser)
 </script>
 
 <style scoped>