feat: Added the ability to add custom themes/languages to Shiki (#2518)

* Replaced `shikiTheme` with `shikiConfig`

* Code.astro now accepts custom themes/langs

* Updated docs

* Updated tests

* Fixed language loading

* Added customization examples

* Updated documentation

* Added more tests

* Changelogs

* Changed some spaces to tabs

* Fixed typo in changesets

* Moved tests fixtures

* Rolled back changes to with-markdown-shiki

* Removed lang example in docs

* Optimized Code component

* Try to fix windows errors

* Try to see if this new tests work

1 files changed, 2 insertions, 2 deletions

diff --git a/packages/markdown/remark/src/index.ts b/packages/markdown/remark/src/index.ts
index 78d645227..e8a315ef1 100644
--- a/packages/markdown/remark/src/index.ts
+++ b/packages/markdown/remark/src/index.ts
@@ -39,7 +39,7 @@ export async function renderMarkdown(content: string, opts?: MarkdownRenderingOp
 	const scopedClassName = opts?.$?.scopedClassName;
 	const mode = opts?.mode ?? 'mdx';
 	const syntaxHighlight = opts?.syntaxHighlight ?? 'prism';
-	const shikiTheme = opts?.shikiTheme ?? 'github-dark';
+	const shikiConfig = opts?.shikiConfig ?? {};
 	const isMDX = mode === 'mdx';
 	const { headers, rehypeCollectHeaders } = createCollectHeaders();
 
@@ -70,7 +70,7 @@ export async function renderMarkdown(content: string, opts?: MarkdownRenderingOp
 	if (syntaxHighlight === 'prism') {
 		parser.use([remarkPrism(scopedClassName)]);
 	} else if (syntaxHighlight === 'shiki') {
-		parser.use([await remarkShiki(shikiTheme)]);
+		parser.use([await remarkShiki(shikiConfig)]);
 	}
 
 	parser.use([[markdownToHtml as any, { allowDangerousHtml: true, passThrough: ['raw', 'mdxTextExpression', 'mdxJsxTextElement', 'mdxJsxFlowElement'] }]]);