feat: browser search engine support

src/app.html

@@ -6,6 +6,12 @@
 		<link rel="manifest" href="%sveltekit.assets%/manifest.json" crossorigin="use-credentials" />
 		<meta name="viewport" content="width=device-width, initial-scale=1, maximum-scale=1" />
 		<meta name="robots" content="noindex,nofollow" />
+		<link
+			rel="search"
+			type="application/opensearchdescription+xml"
+			title="Open WebUI"
+			href="/opensearch.xml"
+		/>
 		<script>
 			// On page load or when changing themes, best to add inline in `head` to avoid FOUC
 			(() => {