build: add precompiled CLI distribution

dist-cli/theme/setup/markdown.ts

@@ -0,0 +1,8 @@
+import { defineMarkdownSetup } from '@slidev/types'
+import markdownItAttrs from 'markdown-it-attrs'
+
+export default defineMarkdownSetup(() => ({
+  markdownItSetup(md) {
+    md.use(markdownItAttrs)
+  },
+}))