Merge PR #73: feat(antigravity): 添加 Antigravity (Cloud AI Companion) 平台支持

新增功能:
- Antigravity OAuth 授权流程支持
- Claude → Gemini 协议转换（Claude API 请求自动转换为 Gemini 格式）
- 配额刷新和状态显示
- 混合调度功能，支持 Anthropic 和 Antigravity 账户混合使用
- /antigravity 专用路由，支持仅使用 Antigravity 账户
- 前端 Antigravity 服务商标识和账户管理功能

冲突解决:
- CreateAccountModal.vue: 合并 data-tour 属性和 mixed-scheduling 属性
- EditAccountModal.vue: 合并 data-tour 属性和 mixed-scheduling 属性

代码质量改进:
- 修复 antigravity 类型文件的 gofmt 格式问题（struct 字段对齐、interface{} → any）
- 移除 .golangci.yml 中的 gofmt 排除规则
- 修复测试文件的格式问题

frontend/src/components/common/GroupSelector.vue

@@ -50,6 +50,7 @@ interface Props {
   modelValue: number[]
   groups: Group[]
   platform?: GroupPlatform // Optional platform filter
+  mixedScheduling?: boolean // For antigravity accounts: allow anthropic/gemini groups
 }
 
 const props = defineProps<Props>()
@@ -62,6 +63,13 @@ const filteredGroups = computed(() => {
   if (!props.platform) {
     return props.groups
   }
+  // antigravity 账户启用混合调度后，可选择 anthropic/gemini 分组
+  if (props.platform === 'antigravity' && props.mixedScheduling) {
+    return props.groups.filter(
+      (g) => g.platform === 'antigravity' || g.platform === 'anthropic' || g.platform === 'gemini'
+    )
+  }
+  // 默认：只能选择同 platform 的分组
   return props.groups.filter((g) => g.platform === props.platform)
 })
 

frontend/src/components/common/PlatformIcon.vue

@@ -15,6 +15,10 @@
   <svg v-else-if="platform === 'gemini'" :class="sizeClass" viewBox="0 0 24 24" fill="currentColor">
     <path d="M12 2l1.89 7.2L21 12l-7.11 2.8L12 22l-1.89-7.2L3 12l7.11-2.8L12 2z" />
   </svg>
+  <!-- Antigravity logo (cloud) -->
+  <svg v-else-if="platform === 'antigravity'" :class="sizeClass" viewBox="0 0 24 24" fill="currentColor">
+    <path d="M19.35 10.04C18.67 6.59 15.64 4 12 4 9.11 4 6.6 5.64 5.35 8.04 2.34 8.36 0 10.91 0 14c0 3.31 2.69 6 6 6h13c2.76 0 5-2.24 5-5 0-2.64-2.05-4.78-4.65-4.96z" />
+  </svg>
   <!-- Fallback: generic platform icon -->
   <svg v-else :class="sizeClass" fill="currentColor" viewBox="0 0 24 24">
     <path

frontend/src/components/common/PlatformTypeBadge.vue

@@ -72,6 +72,7 @@ const props = defineProps<Props>()
 const platformLabel = computed(() => {
   if (props.platform === 'anthropic') return 'Anthropic'
   if (props.platform === 'openai') return 'OpenAI'
+  if (props.platform === 'antigravity') return 'Antigravity'
   return 'Gemini'
 })
 
@@ -95,6 +96,9 @@ const platformClass = computed(() => {
   if (props.platform === 'openai') {
     return 'bg-emerald-100 text-emerald-700 dark:bg-emerald-900/30 dark:text-emerald-400'
   }
+  if (props.platform === 'antigravity') {
+    return 'bg-purple-100 text-purple-700 dark:bg-purple-900/30 dark:text-purple-400'
+  }
   return 'bg-blue-100 text-blue-700 dark:bg-blue-900/30 dark:text-blue-400'
 })
 
@@ -105,6 +109,9 @@ const typeClass = computed(() => {
   if (props.platform === 'openai') {
     return 'bg-emerald-100 text-emerald-600 dark:bg-emerald-900/30 dark:text-emerald-400'
   }
+  if (props.platform === 'antigravity') {
+    return 'bg-purple-100 text-purple-600 dark:bg-purple-900/30 dark:text-purple-400'
+  }
   return 'bg-blue-100 text-blue-600 dark:bg-blue-900/30 dark:text-blue-400'
 })
 </script>