add markdown formatting with code support

src/lib/server/markdown.ts

@@ -0,0 +1,18 @@
+import { Marked } from 'marked';
+import { markedHighlight } from 'marked-highlight';
+import hljs from 'highlight.js';
+
+const marked = new Marked(
+	markedHighlight({
+		emptyLangClass: 'hljs',
+		langPrefix: 'hljs language-',
+		highlight(code, lang) {
+			const language = hljs.getLanguage(lang) ? lang : 'plaintext';
+			return hljs.highlight(code, { language }).value;
+		}
+	})
+);
+
+export function renderMarkdown(content: string): string {
+	return marked.parse(content, { async: false });
+}