fix(frontend): 统一徽标样式并修复 Google One 用量显示

**修复内容：**

1. **统一徽标样式**
   - 所有徽标使用相同的 Tailwind 类
   - Free: gray-100/600, Pro: blue-100/600, Ultra: purple-100/600
   - 暗色模式统一使用 /40 透明度
   - Client 和 AI Studio 都使用蓝色徽标

2. **修复 Google One 用量显示**
   - 后端已为所有 Gemini OAuth (GCP/Google One/Client) 返回用量数据
   - 前端只要有用量数据就显示进度条（移除 isGeminiCodeAssist 限制）
   - Google One 现在也会显示 Pro/Flash 进度条 + 统计数据
   - 只有自定义 Client OAuth 显示「无限流」（无追踪）

**最终显示规则：**
- AI Studio API Key: 「无限流」或「限流 XX」
- Client OAuth: 「无限流」（无追踪）
- GCP OAuth: Pro/Flash 进度条 + 统计
- Google One OAuth: Pro/Flash 进度条 + 统计

frontend/src/components/account/AccountQuotaInfo.vue

@@ -94,41 +94,41 @@ const tierLabel = computed(() => {
   return 'AI Studio'
 })
 
-// Tier Badge 样式
+// Tier Badge 样式（统一样式）
 const tierBadgeClass = computed(() => {
   const creds = props.account.credentials as GeminiCredentials | undefined
 
   if (isCodeAssist.value) {
     // GCP Code Assist 样式
     const tierColorMap: Record<string, string> = {
-      LEGACY: 'bg-gray-100 text-gray-700 dark:bg-gray-900/30 dark:text-gray-400',
+      LEGACY: 'bg-gray-100 text-gray-600 dark:bg-gray-700 dark:text-gray-300',
-      PRO: 'bg-blue-100 text-blue-700 dark:bg-blue-900/30 dark:text-blue-400',
+      PRO: 'bg-blue-100 text-blue-600 dark:bg-blue-900/40 dark:text-blue-300',
-      ULTRA: 'bg-amber-100 text-amber-700 dark:bg-amber-900/30 dark:text-amber-400',
+      ULTRA: 'bg-purple-100 text-purple-600 dark:bg-purple-900/40 dark:text-purple-300',
-      'standard-tier': 'bg-green-100 text-green-700 dark:bg-green-900/30 dark:text-green-400',
+      'standard-tier': 'bg-green-100 text-green-600 dark:bg-green-900/40 dark:text-green-300',
-      'pro-tier': 'bg-blue-100 text-blue-700 dark:bg-blue-900/30 dark:text-blue-400',
+      'pro-tier': 'bg-blue-100 text-blue-600 dark:bg-blue-900/40 dark:text-blue-300',
-      'ultra-tier': 'bg-amber-100 text-amber-700 dark:bg-amber-900/30 dark:text-amber-400'
+      'ultra-tier': 'bg-purple-100 text-purple-600 dark:bg-purple-900/40 dark:text-purple-300'
     }
     return (
       tierColorMap[creds?.tier_id || ''] ||
-      'bg-gray-100 text-gray-700 dark:bg-gray-900/30 dark:text-gray-400'
+      'bg-gray-100 text-gray-600 dark:bg-gray-700 dark:text-gray-300'
     )
   }
 
   if (isGoogleOne.value) {
     // Google One tier 样式
     const tierColorMap: Record<string, string> = {
-      AI_PREMIUM: 'bg-purple-100 text-purple-700 dark:bg-purple-900/30 dark:text-purple-400',
+      AI_PREMIUM: 'bg-purple-100 text-purple-600 dark:bg-purple-900/40 dark:text-purple-300',
-      GOOGLE_ONE_STANDARD: 'bg-blue-100 text-blue-700 dark:bg-blue-900/30 dark:text-blue-400',
+      GOOGLE_ONE_STANDARD: 'bg-blue-100 text-blue-600 dark:bg-blue-900/40 dark:text-blue-300',
-      GOOGLE_ONE_BASIC: 'bg-green-100 text-green-700 dark:bg-green-900/30 dark:text-green-400',
+      GOOGLE_ONE_BASIC: 'bg-green-100 text-green-600 dark:bg-green-900/40 dark:text-green-300',
-      FREE: 'bg-gray-100 text-gray-700 dark:bg-gray-900/30 dark:text-gray-400',
+      FREE: 'bg-gray-100 text-gray-600 dark:bg-gray-700 dark:text-gray-300',
-      GOOGLE_ONE_UNKNOWN: 'bg-gray-100 text-gray-700 dark:bg-gray-900/30 dark:text-gray-400',
+      GOOGLE_ONE_UNKNOWN: 'bg-gray-100 text-gray-600 dark:bg-gray-700 dark:text-gray-300',
-      GOOGLE_ONE_UNLIMITED: 'bg-amber-100 text-amber-700 dark:bg-amber-900/30 dark:text-amber-400'
+      GOOGLE_ONE_UNLIMITED: 'bg-amber-100 text-amber-600 dark:bg-amber-900/40 dark:text-amber-300'
     }
-    return tierColorMap[creds?.tier_id || ''] || 'bg-purple-100 text-purple-700 dark:bg-purple-900/30 dark:text-purple-400'
+    return tierColorMap[creds?.tier_id || ''] || 'bg-gray-100 text-gray-600 dark:bg-gray-700 dark:text-gray-300'
   }
 
   // AI Studio 默认样式：蓝色
-  return 'bg-blue-100 text-blue-700 dark:bg-blue-900/30 dark:text-blue-400'
+  return 'bg-blue-100 text-blue-600 dark:bg-blue-900/40 dark:text-blue-300'
 })
 
 // 是否限流

frontend/src/components/account/AccountUsageCell.vue

@@ -241,8 +241,8 @@
         <div v-else-if="error" class="text-xs text-red-500">
           {{ error }}
         </div>
-        <!-- Code Assist: show model usage bars -->
+        <!-- GCP & Google One: show model usage bars when available -->
-        <div v-else-if="isGeminiCodeAssist && geminiUsageAvailable" class="space-y-1">
+        <div v-else-if="geminiUsageAvailable" class="space-y-1">
           <UsageProgressBar
             v-if="usageInfo?.gemini_pro_daily"
             label="Pro"
@@ -263,7 +263,7 @@
             * {{ t('admin.accounts.gemini.quotaPolicy.simulatedNote') || 'Simulated quota' }}
           </p>
         </div>
-        <!-- AI Studio & Google One: show unlimited flow -->
+        <!-- AI Studio Client OAuth: show unlimited flow (no usage tracking) -->
         <div v-else class="text-xs text-gray-400">
           {{ t('admin.accounts.gemini.rateLimit.unlimited') }}
         </div>
@@ -613,14 +613,14 @@ const geminiAuthTypeLabel = computed(() => {
   return null
 })
 
-// Gemini 账户类型徽章样式
+// Gemini 账户类型徽章样式（统一样式）
 const geminiTierClass = computed(() => {
   const creds = props.account.credentials as GeminiCredentials | undefined
   const oauthType = creds?.oauth_type
 
-  // AI Studio: use neutral gray color (no tier)
+  // Client (自定义 OAuth): 使用蓝色（与 AI Studio 一致）
   if (oauthType === 'ai_studio') {
-    return 'bg-gray-100 text-gray-600 dark:bg-gray-700 dark:text-gray-300'
+    return 'bg-blue-100 text-blue-600 dark:bg-blue-900/40 dark:text-blue-300'
   }
 
   if (!geminiTier.value) return ''