auto-claude: subtask-2-2 - Create WelcomeStep component

Create welcome step component for the onboarding wizard with:
- Welcome message and description
- Feature overview grid with 4 key features (AI-powered dev, spec-driven workflow, memory & context, parallel execution)
- Get Started and Skip Setup action buttons
- Responsive layout following WelcomeScreen.tsx patterns

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

auto-claude-ui/src/renderer/components/onboarding/WelcomeStep.tsx

@@ -0,0 +1,118 @@
+import { Sparkles, Zap, Brain, FileCode } from 'lucide-react';
+import { Button } from '../ui/button';
+import { Card, CardContent } from '../ui/card';
+
+interface WelcomeStepProps {
+  onGetStarted: () => void;
+  onSkip: () => void;
+}
+
+interface FeatureCardProps {
+  icon: React.ReactNode;
+  title: string;
+  description: string;
+}
+
+function FeatureCard({ icon, title, description }: FeatureCardProps) {
+  return (
+    <Card className="border border-border bg-card/50 backdrop-blur-sm">
+      <CardContent className="p-4">
+        <div className="flex items-start gap-3">
+          <div className="flex h-10 w-10 shrink-0 items-center justify-center rounded-lg bg-primary/10 text-primary">
+            {icon}
+          </div>
+          <div>
+            <h3 className="font-medium text-foreground">{title}</h3>
+            <p className="mt-1 text-sm text-muted-foreground">{description}</p>
+          </div>
+        </div>
+      </CardContent>
+    </Card>
+  );
+}
+
+/**
+ * Welcome step component for the onboarding wizard.
+ * Displays a welcome message with a feature overview and actions to get started or skip.
+ */
+export function WelcomeStep({ onGetStarted, onSkip }: WelcomeStepProps) {
+  const features = [
+    {
+      icon: <Sparkles className="h-5 w-5" />,
+      title: 'AI-Powered Development',
+      description: 'Generate code and build features using Claude Code agents'
+    },
+    {
+      icon: <FileCode className="h-5 w-5" />,
+      title: 'Spec-Driven Workflow',
+      description: 'Define tasks with clear specifications and let Auto Claude handle the implementation'
+    },
+    {
+      icon: <Brain className="h-5 w-5" />,
+      title: 'Memory & Context',
+      description: 'Optional Graphiti integration for persistent memory across sessions'
+    },
+    {
+      icon: <Zap className="h-5 w-5" />,
+      title: 'Parallel Execution',
+      description: 'Run multiple agents in parallel for faster development cycles'
+    }
+  ];
+
+  return (
+    <div className="flex h-full flex-col items-center justify-center px-8 py-6">
+      <div className="w-full max-w-2xl">
+        {/* Hero Section */}
+        <div className="text-center mb-8">
+          <h1 className="text-3xl font-bold text-foreground tracking-tight">
+            Welcome to Auto Claude
+          </h1>
+          <p className="mt-3 text-muted-foreground text-lg">
+            Build software autonomously with AI-powered agents
+          </p>
+        </div>
+
+        {/* Features Grid */}
+        <div className="grid grid-cols-1 md:grid-cols-2 gap-4 mb-10">
+          {features.map((feature, index) => (
+            <FeatureCard
+              key={index}
+              icon={feature.icon}
+              title={feature.title}
+              description={feature.description}
+            />
+          ))}
+        </div>
+
+        {/* Description */}
+        <div className="text-center mb-8">
+          <p className="text-muted-foreground">
+            This wizard will help you set up your environment in just a few steps.
+            You can configure your Claude OAuth token, optionally set up memory features,
+            and create your first task.
+          </p>
+        </div>
+
+        {/* Action Buttons */}
+        <div className="flex flex-col sm:flex-row gap-4 justify-center">
+          <Button
+            size="lg"
+            onClick={onGetStarted}
+            className="gap-2 px-8"
+          >
+            <Sparkles className="h-5 w-5" />
+            Get Started
+          </Button>
+          <Button
+            size="lg"
+            variant="ghost"
+            onClick={onSkip}
+            className="text-muted-foreground hover:text-foreground"
+          >
+            Skip Setup
+          </Button>
+        </div>
+      </div>
+    </div>
+  );
+}