feat(antigravity): comprehensive enhancements - model mapping, rate limiting, scheduling & ops

Key changes:
- Upgrade model mapping: Opus 4.5 → Opus 4.6-thinking with precise matching
- Unified rate limiting: scope-level → model-level with Redis snapshot sync
- Load-balanced scheduling by call count with smart retry mechanism
- Force cache billing support
- Model identity injection in prompts with leak prevention
- Thinking mode auto-handling (max_tokens/budget_tokens fix)
- Frontend: whitelist mode toggle, model mapping validation, status indicators
- Gemini session fallback with Redis Trie O(L) matching
- Ops: enhanced concurrency monitoring, account availability, retry logic
- Migration scripts: 049-051 for model mapping unification

frontend/src/components/account/AccountStatusIndicator.vue

@@ -56,6 +56,7 @@
         ></div>
       </div>
     </div>
+
     <!-- Rate Limit Indicator (429) -->
     <div v-if="isRateLimited" class="group relative">
       <span
@@ -89,6 +90,26 @@
           class="pointer-events-none absolute bottom-full left-1/2 z-50 mb-2 -translate-x-1/2 whitespace-nowrap rounded bg-gray-900 px-2 py-1 text-xs text-white opacity-0 transition-opacity group-hover:opacity-100 dark:bg-gray-700"
         >
           {{ t('admin.accounts.status.scopeRateLimitedUntil', { scope: formatScopeName(item.scope), time: formatTime(item.reset_at) }) }}
+          <div
+            class="absolute left-1/2 top-full -translate-x-1/2 border-4 border-transparent border-t-gray-900 dark:border-t-gray-700"          ></div>
+        </div>
+      </div>
+    </template>
+
+    <!-- Model Rate Limit Indicators (Antigravity OAuth Smart Retry) -->
+    <template v-if="activeModelRateLimits.length > 0">
+      <div v-for="item in activeModelRateLimits" :key="item.model" class="group relative">
+        <span
+          class="inline-flex items-center gap-1 rounded bg-purple-100 px-1.5 py-0.5 text-xs font-medium text-purple-700 dark:bg-purple-900/30 dark:text-purple-400"
+        >
+          <Icon name="exclamationTriangle" size="xs" :stroke-width="2" />
+          {{ formatScopeName(item.model) }}
+        </span>
+        <!-- Tooltip -->
+        <div
+          class="pointer-events-none absolute bottom-full left-1/2 z-50 mb-2 -translate-x-1/2 whitespace-nowrap rounded bg-gray-900 px-2 py-1 text-xs text-white opacity-0 transition-opacity group-hover:opacity-100 dark:bg-gray-700"
+        >
+          {{ t('admin.accounts.status.modelRateLimitedUntil', { model: formatScopeName(item.model), time: formatTime(item.reset_at) }) }}
           <div
             class="absolute left-1/2 top-full -translate-x-1/2 border-4 border-transparent border-t-gray-900 dark:border-t-gray-700"
           ></div>
@@ -149,11 +170,28 @@ const activeScopeRateLimits = computed(() => {
     .map(([scope, info]) => ({ scope, reset_at: info.reset_at }))
 })
 
+// Computed: active model rate limits (Antigravity OAuth Smart Retry)
+const activeModelRateLimits = computed(() => {
+  const modelLimits = (props.account.extra as Record<string, unknown> | undefined)?.model_rate_limits as
+    | Record<string, { rate_limited_at: string; rate_limit_reset_at: string }>
+    | undefined
+  if (!modelLimits) return []
+  const now = new Date()
+  return Object.entries(modelLimits)
+    .filter(([, info]) => new Date(info.rate_limit_reset_at) > now)
+    .map(([model, info]) => ({ model, reset_at: info.rate_limit_reset_at }))
+})
+
 const formatScopeName = (scope: string): string => {
   const names: Record<string, string> = {
     claude: 'Claude',
+    claude_sonnet: 'Claude Sonnet',
+    claude_opus: 'Claude Opus',
+    claude_haiku: 'Claude Haiku',
     gemini_text: 'Gemini',
-    gemini_image: 'Image'
+    gemini_image: 'Image',
+    gemini_flash: 'Gemini Flash',
+    gemini_pro: 'Gemini Pro'
   }
   return names[scope] || scope
 }