feat: prioritize new gemini image models in frontend

frontend/src/composables/__tests__/useModelWhitelist.spec.ts

@@ -27,6 +27,15 @@ describe('useModelWhitelist', () => {
 
     expect(models).toContain('gemini-2.5-flash-image')
     expect(models).toContain('gemini-3.1-flash-image')
+    expect(models.indexOf('gemini-3.1-flash-image')).toBeLessThan(models.indexOf('gemini-2.0-flash'))
+    expect(models.indexOf('gemini-2.5-flash-image')).toBeLessThan(models.indexOf('gemini-2.5-flash'))
+  })
+
+  it('antigravity 模型列表会把新的 Gemini 图片模型排在前面', () => {
+    const models = getModelsByPlatform('antigravity')
+
+    expect(models.indexOf('gemini-3.1-flash-image')).toBeLessThan(models.indexOf('gemini-2.5-flash'))
+    expect(models.indexOf('gemini-2.5-flash-image')).toBeLessThan(models.indexOf('gemini-2.5-flash-lite'))
   })
 
   it('whitelist 模式会忽略通配符条目', () => {

frontend/src/composables/useModelWhitelist.ts

@@ -51,13 +51,13 @@ export const claudeModels = [
 const geminiModels = [
   // Keep in sync with backend curated Gemini lists.
   // This list is intentionally conservative (models commonly available across OAuth/API key).
+  'gemini-3.1-flash-image',
+  'gemini-2.5-flash-image',
   'gemini-2.0-flash',
   'gemini-2.5-flash',
-  'gemini-2.5-flash-image',
   'gemini-2.5-pro',
   'gemini-3-flash-preview',
-  'gemini-3-pro-preview',
-  'gemini-3.1-flash-image'
+  'gemini-3-pro-preview'
 ]
 
 // Sora
@@ -87,8 +87,9 @@ const antigravityModels = [
   'claude-sonnet-4-5',
   'claude-sonnet-4-5-thinking',
   // Gemini 2.5 系列
-  'gemini-2.5-flash',
+  'gemini-3.1-flash-image',
   'gemini-2.5-flash-image',
+  'gemini-2.5-flash',
   'gemini-2.5-flash-lite',
   'gemini-2.5-flash-thinking',
   'gemini-2.5-pro',
@@ -99,7 +100,6 @@ const antigravityModels = [
   // Gemini 3.1 系列
   'gemini-3.1-pro-high',
   'gemini-3.1-pro-low',
-  'gemini-3.1-flash-image',
   'gemini-3-pro-image',
   // 其他
   'gpt-oss-120b-medium',