fix: v0.11.1 隐藏 AirDrama Fast 选项（火山未开通）

- Toolbar modelItems 注释掉 Fast 选项，用户只能选标准版
- 外部团队测试时选 Fast 会报 model not found 错误

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

web/src/components/Toolbar.tsx

@@ -72,7 +72,8 @@ const generationTypeItems = [
 
 const modelItems = [
   { label: 'AirDrama', value: 'seedance_2.0' as ModelOption, icon: <DiamondIcon /> },
-  { label: 'AirDrama Fast', value: 'seedance_2.0_fast' as ModelOption, icon: <LightningIcon /> },
+  // Fast 暂未开通，隐藏选项
+  // { label: 'AirDrama Fast', value: 'seedance_2.0_fast' as ModelOption, icon: <LightningIcon /> },
 ];
 
 const modeItems = [