Add basic necessary SEO tags

web-app/src/lib/templates/common/Head.svelte

@@ -2,8 +2,14 @@
   const {
     title,
     favicon,
-    nestingLevel = 0
-  }: { title: string; favicon: string; nestingLevel?: number } = $props();
+    nestingLevel = 0,
+    metaDescription = null
+  }: {
+    title: string;
+    favicon: string;
+    nestingLevel?: number;
+    metaDescription: string | null;
+  } = $props();
 </script>
 
 <svelte:head>
@@ -11,6 +17,7 @@
     <meta charset="UTF-8" />
     <meta name="viewport" content="width=device-width, initial-scale=1.0" />
     <title>{title}</title>
+    <meta name="description" content={metaDescription ?? title} />
     <link rel="stylesheet" href={`${"../".repeat(nestingLevel)}styles.css`} />
     {#if favicon}
       <link rel="icon" href={favicon} />