fix(web-shell): encode vision model picker selection & polish dispatch

packages/web-shell/client/App.tsx

@@ -218,6 +218,14 @@ const COMPACT_MODE_SETTING_KEY = 'ui.compactMode';
 const HIDE_TIPS_SETTING_KEY = 'ui.hideTips';
 const HIDDEN_COMPOSER_MODEL_IDS = new Set(['coder-model(qwen-oauth)']);
 
+/** Maps each ModelDialogMode to its i18n title key — single source of truth. */
+const MODE_TITLE_KEY: Record<ModelDialogMode, string> = {
+  main: 'model.select',
+  fast: 'model.setFast',
+  voice: 'model.setVoice',
+  vision: 'model.setVision',
+};
+
 function isVisibleComposerModel(model: { id: string }): boolean {
   return !HIDDEN_COMPOSER_MODEL_IDS.has(model.id);
 }
@@ -1650,6 +1658,12 @@ export function App({
     )?.values.effective;
     return typeof value === 'string' && value.trim() ? value.trim() : undefined;
   })();
+  const currentVisionModel = (() => {
+    const value = workspaceSettings.find(
+      (setting) => setting.key === 'visionModel',
+    )?.values.effective;
+    return typeof value === 'string' && value.trim() ? value.trim() : undefined;
+  })();
   const shellOutputMaxLines = resolveShellOutputMaxLines(workspaceSettings);
   const [compactMode, setCompactMode] = useState(false);
   const compactModeRef = useRef(compactMode);
@@ -3315,7 +3329,11 @@ export function App({
 
   const handleVisionModelSelect = useCallback(
     (modelId: string) => {
-      setWorkspaceSetting('workspace', 'visionModel', modelId).catch(
+      // Model IDs from the picker arrive in ACP format: `modelId(authType)`.
+      // Core's resolveVisionModelSelection() expects `authType:modelId`.
+      const match = modelId.match(/^(.+)\(([^()]+)\)$/);
+      const encoded = match ? `${match[2]}:${match[1]}` : modelId;
+      setWorkspaceSetting('workspace', 'visionModel', encoded).catch(
         (error: unknown) => reportError(error, t('model.setVision')),
       );
     },
@@ -3456,34 +3474,31 @@ export function App({
           )}
           {modelDialogMode && (
             <DialogShell
-              title={
-                modelDialogMode === 'fast'
-                  ? t('model.setFast')
-                  : modelDialogMode === 'voice'
-                    ? t('model.setVoice')
-                    : modelDialogMode === 'vision'
-                      ? t('model.setVision')
-                      : t('model.select')
-              }
+              title={t(MODE_TITLE_KEY[modelDialogMode])}
               size="lg"
               onClose={() => setModelDialogMode(null)}
             >
               <ModelDialog
                 mode={modelDialogMode}
                 models={modelDialogMode === 'voice' ? voiceModels : undefined}
                 currentModelId={
-                  modelDialogMode === 'voice' ? currentVoiceModel : undefined
+                  modelDialogMode === 'voice'
+                    ? currentVoiceModel
+                    : modelDialogMode === 'vision'
+                      ? currentVisionModel
+                      : undefined
                 }
                 onSelect={(modelId) => {
-                  if (modelDialogMode === 'fast') {
-                    handleFastModelSelect(modelId);
-                  } else if (modelDialogMode === 'voice') {
-                    handleVoiceModelSelect(modelId);
-                  } else if (modelDialogMode === 'vision') {
-                    handleVisionModelSelect(modelId);
-                  } else {
-                    handleModelSelect(modelId);
-                  }
+                  const handlers: Record<
+                    ModelDialogMode,
+                    (id: string) => void
+                  > = {
+                    main: handleModelSelect,
+                    fast: handleFastModelSelect,
+                    voice: handleVoiceModelSelect,
+                    vision: handleVisionModelSelect,
+                  };
+                  handlers[modelDialogMode ?? 'main'](modelId);
                   setModelDialogMode(null);
                 }}
               />

packages/web-shell/client/i18n.tsx

@@ -1209,6 +1209,9 @@ const EN: Messages = {
     'Frontend-only chat content width. Stored in this browser.',
   'settings.option.ui.chatWidth.1000': 'Regular',
   'settings.option.ui.chatWidth.wide': 'Ultra wide',
+  'settings.label.visionModel': 'Vision Model',
+  'settings.description.visionModel':
+    'Image-capable model used as the vision bridge. Leave empty to auto-select.',
   'welcome.changeModel': '(/model to change)',
   'welcome.defaultModel': 'unknown model',
   'welcome.modeHint': 'Shift+Tab or /approval-mode',
@@ -2442,6 +2445,9 @@ const ZH: Messages = {
   'settings.label.fastModel': '快速模型',
   'settings.description.fastModel':
     '用于生成提示建议和推测执行的模型。留空则使用主模型。较小/更快的模型（例如 qwen3-coder-flash）可以降低延迟和成本。',
+  'settings.label.visionModel': '视觉模型',
+  'settings.description.visionModel':
+    '用于视觉桥接的图像能力模型。留空则自动选择。',
   'settings.label.context.fileFiltering.respectGitIgnore': '遵守 .gitignore',
   'settings.description.context.fileFiltering.respectGitIgnore':
     '搜索时遵守 .gitignore 文件。',