Migrate SvelteKit to the latest version 431 (#526)

web/src/routes/+layout.svelte

@@ -0,0 +1,42 @@
+<script lang="ts">
+	import '../app.css';
+
+	import { fade } from 'svelte/transition';
+	import DownloadPanel from '$lib/components/asset-viewer/download-panel.svelte';
+	import AnnouncementBox from '$lib/components/shared-components/announcement-box.svelte';
+	import UploadPanel from '$lib/components/shared-components/upload-panel.svelte';
+	import { onMount } from 'svelte';
+	import { checkAppVersion } from '$lib/utils/check-app-version';
+	import { page } from '$app/stores';
+
+	let shouldShowAnnouncement: boolean;
+	let localVersion: string;
+	let remoteVersion: string;
+
+	onMount(async () => {
+		const res = await checkAppVersion();
+
+		shouldShowAnnouncement = res.shouldShowAnnouncement;
+		localVersion = res.localVersion ?? 'unknown';
+		remoteVersion = res.remoteVersion ?? 'unknown';
+	});
+</script>
+
+<main>
+	{#key $page.url}
+		<div in:fade={{ duration: 100 }}>
+			<slot />
+			<DownloadPanel />
+
+			<UploadPanel />
+
+			{#if shouldShowAnnouncement}
+				<AnnouncementBox
+					{localVersion}
+					{remoteVersion}
+					on:close={() => (shouldShowAnnouncement = false)}
+				/>
+			{/if}
+		</div>
+	{/key}
+</main>