Make markdown headings optional to Main layout

src/layouts/Main.astro

@@ -8,7 +8,7 @@ import TableOfContents from "@components/TableOfContents.astro";
 import type { MarkdownHeading } from "astro";
 
 type Props = Pick<CollectionEntry<"handbook">["data"], "title" | "description"> & {
-  headings: MarkdownHeading[];
+  headings?: MarkdownHeading[];
 };
 
 const { title, description, headings } = Astro.props;

src/pages/index.astro

@@ -10,6 +10,6 @@ import Main from '@layouts/Main.astro';
 // 	(a, b) => a.data.pubDate.valueOf() - b.data.pubDate.valueOf()
 // );
 ---
-<Main title="test" description='test' headings={[]}>
+<Main title="test" description='test'>
 	Nothing here yet.
 </Main>