add Banner component

src/routes/+page.svelte

@@ -79,6 +79,20 @@
 	<title>sui</title>
 </svelte:head>
 
+<!-- Cookie Consent Banner Demo -->
+<Banner
+	title="Manage Cookies"
+	controls={{
+		moreInfo: { label: 'More Info', type: 'link', href: '#!' }
+	}}
+	onaccept={() => console.log('Cookies accepted!')}
+	ondecline={() => console.log('Cookies declined!')}
+	open
+>
+	We use cookies and similar technologies to enhance your experience, analyze site traffic, and
+	measure our ads. You can manage your preferences anytime.
+</Banner>
+
 <h1 class="mb-4 text-3xl font-bold">sui — Opinionated Svelte 5 UI toolkit</h1>
 
 <p class="mb-4">