Use {group} in textContentMappings

[Huxpro]

What package is the feature request related to?

typedoc-plugin-markdown

Background

@group is useful to simulate custom member types, e.g. @group Events, @group Components.

By allowing the use of {group}, it will be convenient to title file as Event: onClick or Component: Button() via textContentMappings.

Proposed solution

Support {group} in textContentMappings, or even a callback that does the string interpolation?

Maybe it's better to build a custom theme for this use case?

[tgreyuk]

In typedoc-plugin-markdown@4.3.0 you can do the following with a JS config file:

 pageTitleTemplates: {
    member: (args) => `${args.group.slice(0, -1)}: ${args.name}`,
  },

Example:

https://github.com/typedoc2md/typedoc-plugin-markdown-scratchpad/blob/main/issues/715/docs/md/functions/Button.md