feat(worktree): add AI commit message generation feature

- Implemented a new endpoint to generate commit messages based on git diffs.
- Updated worktree routes to include the AI commit message generation functionality.
- Enhanced the UI to support automatic generation of commit messages when the commit dialog opens, based on user settings.
- Added settings for enabling/disabling AI-generated commit messages and configuring the model used for generation.

apps/ui/src/components/views/board-view/dialogs/commit-worktree-dialog.tsx

@@ -13,6 +13,7 @@ import { Label } from '@/components/ui/label';
 import { GitCommit, Loader2, Sparkles } from 'lucide-react';
 import { getElectronAPI } from '@/lib/electron';
 import { toast } from 'sonner';
+import { useAppStore } from '@/store/app-store';
 
 interface WorktreeInfo {
   path: string;
@@ -39,6 +40,7 @@ export function CommitWorktreeDialog({
   const [isLoading, setIsLoading] = useState(false);
   const [isGenerating, setIsGenerating] = useState(false);
   const [error, setError] = useState<string | null>(null);
+  const enableAiCommitMessages = useAppStore((state) => state.enableAiCommitMessages);
 
   const handleCommit = async () => {
     if (!worktree || !message.trim()) return;
@@ -83,19 +85,24 @@ export function CommitWorktreeDialog({
     }
   };
 
-  // Generate AI commit message when dialog opens
+  // Generate AI commit message when dialog opens (if enabled)
   useEffect(() => {
     if (open && worktree) {
       // Reset state
       setMessage('');
       setError(null);
+
+      // Only generate AI commit message if enabled
+      if (!enableAiCommitMessages) {
+        return;
+      }
+
       setIsGenerating(true);
 
       const generateMessage = async () => {
         try {
           const api = getElectronAPI();
           if (!api?.worktree?.generateCommitMessage) {
-            setError('AI commit message generation not available');
             setIsGenerating(false);
             return;
           }
@@ -120,7 +127,7 @@ export function CommitWorktreeDialog({
 
       generateMessage();
     }
-  }, [open, worktree]);
+  }, [open, worktree, enableAiCommitMessages]);
 
   if (!worktree) return null;
 

apps/ui/src/components/views/settings-view.tsx

@@ -44,6 +44,8 @@ export function SettingsView() {
     setEnableDependencyBlocking,
     skipVerificationInAutoMode,
     setSkipVerificationInAutoMode,
+    enableAiCommitMessages,
+    setEnableAiCommitMessages,
     useWorktrees,
     setUseWorktrees,
     muteDoneSound,
@@ -182,11 +184,13 @@ export function SettingsView() {
             skipVerificationInAutoMode={skipVerificationInAutoMode}
             defaultPlanningMode={defaultPlanningMode}
             defaultRequirePlanApproval={defaultRequirePlanApproval}
+            enableAiCommitMessages={enableAiCommitMessages}
             onDefaultSkipTestsChange={setDefaultSkipTests}
             onEnableDependencyBlockingChange={setEnableDependencyBlocking}
             onSkipVerificationInAutoModeChange={setSkipVerificationInAutoMode}
             onDefaultPlanningModeChange={setDefaultPlanningMode}
             onDefaultRequirePlanApprovalChange={setDefaultRequirePlanApproval}
+            onEnableAiCommitMessagesChange={setEnableAiCommitMessages}
           />
         );
       case 'worktrees':

apps/ui/src/components/views/settings-view/feature-defaults/feature-defaults-section.tsx

@@ -10,6 +10,7 @@ import {
   ScrollText,
   ShieldCheck,
   FastForward,
+  Sparkles,
 } from 'lucide-react';
 import { cn } from '@/lib/utils';
 import {
@@ -28,11 +29,13 @@ interface FeatureDefaultsSectionProps {
   skipVerificationInAutoMode: boolean;
   defaultPlanningMode: PlanningMode;
   defaultRequirePlanApproval: boolean;
+  enableAiCommitMessages: boolean;
   onDefaultSkipTestsChange: (value: boolean) => void;
   onEnableDependencyBlockingChange: (value: boolean) => void;
   onSkipVerificationInAutoModeChange: (value: boolean) => void;
   onDefaultPlanningModeChange: (value: PlanningMode) => void;
   onDefaultRequirePlanApprovalChange: (value: boolean) => void;
+  onEnableAiCommitMessagesChange: (value: boolean) => void;
 }
 
 export function FeatureDefaultsSection({
@@ -41,11 +44,13 @@ export function FeatureDefaultsSection({
   skipVerificationInAutoMode,
   defaultPlanningMode,
   defaultRequirePlanApproval,
+  enableAiCommitMessages,
   onDefaultSkipTestsChange,
   onEnableDependencyBlockingChange,
   onSkipVerificationInAutoModeChange,
   onDefaultPlanningModeChange,
   onDefaultRequirePlanApprovalChange,
+  onEnableAiCommitMessagesChange,
 }: FeatureDefaultsSectionProps) {
   return (
     <div
@@ -251,6 +256,34 @@ export function FeatureDefaultsSection({
             </p>
           </div>
         </div>
+
+        {/* Separator */}
+        <div className="border-t border-border/30" />
+
+        {/* AI Commit Messages Setting */}
+        <div className="group flex items-start space-x-3 p-3 rounded-xl hover:bg-accent/30 transition-colors duration-200 -mx-3">
+          <Checkbox
+            id="enable-ai-commit-messages"
+            checked={enableAiCommitMessages}
+            onCheckedChange={(checked) => onEnableAiCommitMessagesChange(checked === true)}
+            className="mt-1"
+            data-testid="enable-ai-commit-messages-checkbox"
+          />
+          <div className="space-y-1.5">
+            <Label
+              htmlFor="enable-ai-commit-messages"
+              className="text-foreground cursor-pointer font-medium flex items-center gap-2"
+            >
+              <Sparkles className="w-4 h-4 text-brand-500" />
+              Generate AI commit messages
+            </Label>
+            <p className="text-xs text-muted-foreground/80 leading-relaxed">
+              When enabled, opening the commit dialog will automatically generate a commit message
+              using AI based on your staged or unstaged changes. You can configure the model used in
+              Model Defaults.
+            </p>
+          </div>
+        </div>
       </div>
     </div>
   );

apps/ui/src/components/views/settings-view/model-defaults/model-defaults-section.tsx

@@ -28,6 +28,11 @@ const QUICK_TASKS: PhaseConfig[] = [
     label: 'Image Descriptions',
     description: 'Analyzes and describes context images',
   },
+  {
+    key: 'commitMessageModel',
+    label: 'Commit Messages',
+    description: 'Generates git commit messages from diffs',
+  },
 ];
 
 const VALIDATION_TASKS: PhaseConfig[] = [