Add Markdown editor field type for editing text

[lane711]

This will be used for editing content such as blog post body content.

We need to find a suitable open source markdown editor such as:

1. https://github.com/marktext/marktext
2. https://mdxeditor.dev/

Developers will need to be able to specify that they want to use the markdown editor while editing certain fields, ie:

export const fields: ApiConfig["fields"] = {
  body: {
    type: "mdxEditor",
  },
}

[PeteJStewart]

I'll make a start on this feature.
@lane711 Are there any specific parts of the code you can point me to for this feature, such as tests or examples of other custom field type?

[lane711]

Sure!

Usage in schema:
https://github.com/lane711/sonicjs/blob/main/src/custom/db/schema/posts.ts#L115

Example text area:
https://github.com/lane711/sonicjs/blob/main/src/pages/admin/forms/fields/text-area.astro

Add a reference to new markdown field here:
https://github.com/lane711/sonicjs/blob/main/src/pages/admin/forms/form-component.astro#L27