fix(grammer): nesting andnative markdown highlighting in MDC grammer

[farnabaz]

Change MDC grammer to allow standalone usage. The current state is designed to inject into markdown grammar which is suitable for standalone use like Shiki

Before:

After:

Here is the markdown that you can test with:

---
data: value
---

::Grid{cols="3"}
  :::GridCard{#html-id .some-class}
  ...
  :::

  :::GridCard{#html-id2 .some-class}
  ...
  :::

  :::GridCard{#html-id3 .some-class}
  ---
  icon: information
  ---
  Use Vue components in Markdown files, with props, slots
  and nested components with our improved Markdown syntax.

  #header

  Markdown with Components
  :::
::

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[antfu]

Did you change the source? This is a script that fetch upstream grammar and automatically updates on daily-basis

[farnabaz]

I didn't notice that grammar is updating automatically.

But the thing is we can't use MDC grammar from vscode extension, because as I said, it is designed to inject into VSCode markdown language, and using it as standalone grammar will lead to highlight issues.

I will update vscode-mdc, add another grammar for standalone usage, and update this PR