Allow changing language using lang url parameter

Author: Sanqui

src/routes/+layout.svelte

@@ -1,4 +1,5 @@
 <script lang="ts">	
+	import { lang } from '../stores.js';
 	import Meta from '$lib/Meta.svelte';
 	import Header from '$lib/Header.svelte';
 	import Footer from '$lib/Footer.svelte';
@@ -8,6 +9,15 @@
 	}
 
 	let { children }: Props = $props();
+
+	if (typeof window !== 'undefined') {
+		const url = new URL(window.location.href);
+		const url_lang = url.searchParams.get('lang');
+		if (url_lang) {
+			console.log('setting language to', url_lang, 'due to lang url param');
+			lang.set(url_lang);
+		}
+	}
 </script>
 
 <Meta title="" />