Vision model support for Qwen-OAuth (#525)

* refactor: openaiContentGenerator

* refactor: optimize stream handling

* refactor: re-organize refactored files

* fix: unit test cases

* feat: `/model` command for switching to vision model

* fix: lint error

* feat: add image tokenizer to fit vlm context window

* fix: lint and type errors

* feat: add `visionModelPreview` to control default visibility of vision models

* fix: remove deprecated files

* fix: align supported image formats with bailian doc

packages/cli/src/config/settingsSchema.ts

@@ -741,6 +741,16 @@ export const SETTINGS_SCHEMA = {
         description: 'Enable extension management features.',
         showInDialog: false,
       },
+      visionModelPreview: {
+        type: 'boolean',
+        label: 'Vision Model Preview',
+        category: 'Experimental',
+        requiresRestart: false,
+        default: false,
+        description:
+          'Enable vision model support and auto-switching functionality. When disabled, vision models like qwen-vl-max-latest will be hidden and auto-switching will not occur.',
+        showInDialog: true,
+      },
     },
   },