fix(gemini): 更新 Gemini 模型列表配置

- 移除已弃用的 1.5 系列模型
- 调整模型优先级顺序（2.0 Flash > 2.5 Flash > 2.5 Pro > 3.0 Preview）
- 同步前后端模型配置
- 更新相关测试用例和默认模型选择逻辑

frontend/src/components/account/AccountTestModal.vue

@@ -292,8 +292,11 @@ const loadAvailableModels = async () => {
     if (availableModels.value.length > 0) {
       if (props.account.platform === 'gemini') {
         const preferred =
+          availableModels.value.find((m) => m.id === 'gemini-2.0-flash') ||
+          availableModels.value.find((m) => m.id === 'gemini-2.5-flash') ||
           availableModels.value.find((m) => m.id === 'gemini-2.5-pro') ||
-          availableModels.value.find((m) => m.id === 'gemini-3-pro')
+          availableModels.value.find((m) => m.id === 'gemini-3-flash-preview') ||
+          availableModels.value.find((m) => m.id === 'gemini-3-pro-preview')
         selectedModelId.value = preferred?.id || availableModels.value[0].id
       } else {
         // Try to select Sonnet as default, otherwise use first model

frontend/src/components/admin/account/AccountTestModal.vue

@@ -232,8 +232,11 @@ const loadAvailableModels = async () => {
     if (availableModels.value.length > 0) {
       if (props.account.platform === 'gemini') {
         const preferred =
+          availableModels.value.find((m) => m.id === 'gemini-2.0-flash') ||
+          availableModels.value.find((m) => m.id === 'gemini-2.5-flash') ||
           availableModels.value.find((m) => m.id === 'gemini-2.5-pro') ||
-          availableModels.value.find((m) => m.id === 'gemini-3-pro')
+          availableModels.value.find((m) => m.id === 'gemini-3-flash-preview') ||
+          availableModels.value.find((m) => m.id === 'gemini-3-pro-preview')
         selectedModelId.value = preferred?.id || availableModels.value[0].id
       } else {
         // Try to select Sonnet as default, otherwise use first model

frontend/src/components/keys/UseKeyModal.vue

@@ -443,7 +443,7 @@ $env:ANTHROPIC_AUTH_TOKEN="${apiKey}"`
 }
 
 function generateGeminiCliContent(baseUrl: string, apiKey: string): FileConfig {
-  const model = 'gemini-2.5-pro'
+  const model = 'gemini-2.0-flash'
   const modelComment = t('keys.useKeyModal.gemini.modelComment')
   let path: string
   let content: string
@@ -548,14 +548,22 @@ function generateOpenCodeConfig(platform: string, baseUrl: string, apiKey: strin
     }
   }
   const geminiModels = {
-    'gemini-3-pro-high': { name: 'Gemini 3 Pro High' },
-    'gemini-3-pro-low': { name: 'Gemini 3 Pro Low' },
-    'gemini-3-pro-preview': { name: 'Gemini 3 Pro Preview' },
-    'gemini-3-pro-image': { name: 'Gemini 3 Pro Image' },
-    'gemini-3-flash': { name: 'Gemini 3 Flash' },
-    'gemini-2.5-flash-thinking': { name: 'Gemini 2.5 Flash Thinking' },
+    'gemini-2.0-flash': { name: 'Gemini 2.0 Flash' },
     'gemini-2.5-flash': { name: 'Gemini 2.5 Flash' },
-    'gemini-2.5-flash-lite': { name: 'Gemini 2.5 Flash Lite' }
+    'gemini-2.5-pro': { name: 'Gemini 2.5 Pro' },
+    'gemini-3-flash-preview': { name: 'Gemini 3 Flash Preview' },
+    'gemini-3-pro-preview': { name: 'Gemini 3 Pro Preview' }
+  }
+
+  const antigravityGeminiModels = {
+    'gemini-2.5-flash': { name: 'Gemini 2.5 Flash' },
+    'gemini-2.5-flash-lite': { name: 'Gemini 2.5 Flash Lite' },
+    'gemini-2.5-flash-thinking': { name: 'Gemini 2.5 Flash Thinking' },
+    'gemini-3-flash': { name: 'Gemini 3 Flash' },
+    'gemini-3-pro-low': { name: 'Gemini 3 Pro Low' },
+    'gemini-3-pro-high': { name: 'Gemini 3 Pro High' },
+    'gemini-3-pro-preview': { name: 'Gemini 3 Pro Preview' },
+    'gemini-3-pro-image': { name: 'Gemini 3 Pro Image' }
   }
   const claudeModels = {
     'claude-opus-4-5-thinking': { name: 'Claude Opus 4.5 Thinking' },
@@ -575,7 +583,7 @@ function generateOpenCodeConfig(platform: string, baseUrl: string, apiKey: strin
   } else if (platform === 'antigravity-gemini') {
     provider[platform].npm = '@ai-sdk/google'
     provider[platform].name = 'Antigravity (Gemini)'
-    provider[platform].models = geminiModels
+    provider[platform].models = antigravityGeminiModels
   } else if (platform === 'openai') {
     provider[platform].models = openaiModels
   }

frontend/src/composables/useModelWhitelist.ts

@@ -43,13 +43,13 @@ export const claudeModels = [
 
 // Google Gemini
 const geminiModels = [
-  'gemini-2.0-flash', 'gemini-2.0-flash-lite-preview', 'gemini-2.0-flash-exp',
-  'gemini-2.0-pro-exp', 'gemini-2.0-flash-thinking-exp',
-  'gemini-2.5-pro-exp-03-25', 'gemini-2.5-pro-preview-03-25',
-  'gemini-3-pro-preview',
-  'gemini-1.5-pro', 'gemini-1.5-pro-latest',
-  'gemini-1.5-flash', 'gemini-1.5-flash-latest', 'gemini-1.5-flash-8b',
-  'gemini-exp-1206'
+  // Keep in sync with backend curated Gemini lists.
+  // This list is intentionally conservative (models commonly available across OAuth/API key).
+  'gemini-2.0-flash',
+  'gemini-2.5-flash',
+  'gemini-2.5-pro',
+  'gemini-3-flash-preview',
+  'gemini-3-pro-preview'
 ]
 
 // 智谱 GLM
@@ -229,9 +229,8 @@ const openaiPresetMappings = [
 
 const geminiPresetMappings = [
   { label: 'Flash 2.0', from: 'gemini-2.0-flash', to: 'gemini-2.0-flash', color: 'bg-blue-100 text-blue-700 hover:bg-blue-200 dark:bg-blue-900/30 dark:text-blue-400' },
-  { label: 'Flash Lite', from: 'gemini-2.0-flash-lite-preview', to: 'gemini-2.0-flash-lite-preview', color: 'bg-indigo-100 text-indigo-700 hover:bg-indigo-200 dark:bg-indigo-900/30 dark:text-indigo-400' },
-  { label: '1.5 Pro', from: 'gemini-1.5-pro', to: 'gemini-1.5-pro', color: 'bg-purple-100 text-purple-700 hover:bg-purple-200 dark:bg-purple-900/30 dark:text-purple-400' },
-  { label: '1.5 Flash', from: 'gemini-1.5-flash', to: 'gemini-1.5-flash', color: 'bg-emerald-100 text-emerald-700 hover:bg-emerald-200 dark:bg-emerald-900/30 dark:text-emerald-400' }
+  { label: '2.5 Flash', from: 'gemini-2.5-flash', to: 'gemini-2.5-flash', color: 'bg-indigo-100 text-indigo-700 hover:bg-indigo-200 dark:bg-indigo-900/30 dark:text-indigo-400' },
+  { label: '2.5 Pro', from: 'gemini-2.5-pro', to: 'gemini-2.5-pro', color: 'bg-purple-100 text-purple-700 hover:bg-purple-200 dark:bg-purple-900/30 dark:text-purple-400' }
 ]
 
 // =====================