fix(welcome): make WelcomeScreen support isCompact prop to prevent full-screen CSS clash when rendering inside saved-ID wrapper card in App.tsx

Per PLAN item 8. Saved users now get a clean compact welcome prompt without double min-h-screen divs.

frontend/src/App.tsx

@@ -80,7 +80,7 @@ export default function App() {
   if (!identified && !loadingPrefs) {
     const savedId = localStorage.getItem('kira-user-id');
     if (!savedId) {
-      return <WelcomeScreen onComplete={handleWelcome} />;
+      return <WelcomeScreen onComplete={handleWelcome} isCompact />;
     }
     // Has saved ID but not identified yet — show welcome with their name
     return (
@@ -92,7 +92,7 @@ export default function App() {
             </div>
           </div>
           <p className="text-kira-plum/60 text-sm">coming back? say your name to pick up where you left off</p>
-          <WelcomeScreen onComplete={handleWelcome} />
+          <WelcomeScreen onComplete={handleWelcome} isCompact />
         </div>
         <style>{`
           @keyframes pulse-glow {

frontend/src/components/WelcomeScreen.tsx

@@ -2,9 +2,10 @@ import { useState } from 'react';
 
 interface Props {
   onComplete: (name: string) => void;
+  isCompact?: boolean;
 }
 
-export default function WelcomeScreen({ onComplete }: Props) {
+export default function WelcomeScreen({ onComplete, isCompact = false }: Props) {
   const [name, setName] = useState('');
 
   const handleSubmit = (e: React.FormEvent) => {
@@ -13,9 +14,8 @@ export default function WelcomeScreen({ onComplete }: Props) {
     if (trimmed) onComplete(trimmed);
   };
 
-  return (
-    <div className="min-h-screen flex items-center justify-center bg-gradient-to-br from-kira-bg via-kira-glow to-kira-pink/20 p-4">
-      <div className="glass-card max-w-md w-full p-8 text-center space-y-6">
+  const content = (
+    <>
       {/* Avatar preview */}
       <div className="flex justify-center">
         <div className="w-20 h-20 rounded-full bg-gradient-to-br from-kira-pink via-kira-lav to-kira-mint p-1 animate-pulse-glow">
@@ -61,8 +61,22 @@ export default function WelcomeScreen({ onComplete }: Props) {
       <p className="text-[10px] text-kira-plum/30">
         everything stays between us — your name, your preferences, your focus vibes
       </p>
-      </div>
+    </>
+  );
 
+  if (isCompact) {
+    return (
+      <div className="glass-card max-w-md w-full p-8 text-center space-y-6">
+        {content}
+      </div>
+    );
+  }
+
+  return (
+    <div className="min-h-screen flex items-center justify-center bg-gradient-to-br from-kira-bg via-kira-glow to-kira-pink/20 p-4">
+      <div className="glass-card max-w-md w-full p-8 text-center space-y-6">
+        {content}
+      </div>
       <style>{`
         @keyframes pulse-glow {
           0%, 100% { box-shadow: 0 0 12px rgba(255,182,193,0.3); }