perf(ui): hoist marked.use() to module scope to prevent extension stacking (#25837)

src/lib/components/chat/Messages/Markdown.svelte

@@ -1,19 +1,41 @@
-<script>
+<script context="module">
-	import { onDestroy } from 'svelte';
 	import { marked } from 'marked';
-	import { replaceTokens, processResponseContent } from '$lib/utils';
-	import { user } from '$lib/stores';
 
 	import markedExtension from '$lib/utils/marked/extension';
 	import markedKatexExtension from '$lib/utils/marked/katex-extension';
 	import { disableSingleTilde } from '$lib/utils/marked/strikethrough-extension';
 	import { mentionExtension } from '$lib/utils/marked/mention-extension';
 	import colonFenceExtension from '$lib/utils/marked/colon-fence-extension';
-
-	import MarkdownTokens from './Markdown/MarkdownTokens.svelte';
 	import footnoteExtension from '$lib/utils/marked/footnote-extension';
 	import citationExtension from '$lib/utils/marked/citation-extension';
 
+	const options = {
+		throwOnError: false,
+		breaks: true
+	};
+
+	marked.use(markedKatexExtension(options));
+	marked.use(markedExtension(options));
+	marked.use(citationExtension(options));
+	marked.use(footnoteExtension(options));
+	marked.use(colonFenceExtension(options));
+	marked.use(disableSingleTilde);
+	marked.use({
+		extensions: [
+			mentionExtension({ triggerChar: '@' }),
+			mentionExtension({ triggerChar: '#' }),
+			mentionExtension({ triggerChar: '$' })
+		]
+	});
+</script>
+
+<script>
+	import { onDestroy } from 'svelte';
+	import { replaceTokens, processResponseContent } from '$lib/utils';
+	import { user } from '$lib/stores';
+
+	import MarkdownTokens from './Markdown/MarkdownTokens.svelte';
+
 	export let id = '';
 	export let content;
 	export let done = true;
@@ -41,25 +63,6 @@
 	let lastContent = '';
 	let lastParsedContent = '';
 
-	const options = {
-		throwOnError: false,
-		breaks: true
-	};
-
-	marked.use(markedKatexExtension(options));
-	marked.use(markedExtension(options));
-	marked.use(citationExtension(options));
-	marked.use(footnoteExtension(options));
-	marked.use(colonFenceExtension(options));
-	marked.use(disableSingleTilde);
-	marked.use({
-		extensions: [
-			mentionExtension({ triggerChar: '@' }),
-			mentionExtension({ triggerChar: '#' }),
-			mentionExtension({ triggerChar: '$' })
-		]
-	});
-
 	const parseTokens = () => {
 		if (content === lastContent) return;
 		lastContent = content;