fix(alert): normalize optional title prop

Author: vib-tools

src/components/feedback/Alert/Alert.astro

@@ -3,4 +3,4 @@ import Callout from '@/components/documentation/Callout';
 type Props = Readonly<{ title?: string; variant?: 'info' | 'success' | 'warning' | 'danger' }>;
 const { title, variant = 'info' } = Astro.props;
 ---
-<Callout {title} {variant}><slot /></Callout>
+<Callout title={title ?? ''} {variant}><slot /></Callout>