[WIP] Add support for type parameters in generic methods

[Copilot]

Thanks for asking me to work on this. I will get started on it and keep this PR's description up to date as I form a plan and make progress.

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This section details on the original issue you should resolve

<issue_title>Generic method type parameter support</issue_title>
<issue_description>PR PowerShell/PowerShell#12412 (comment) introduced support for supplying type parameters to generic methods, e.g.:

[Array]::Empty[int]()

While it kind of looks like it's already working ([int] is being highlighted the same way as [Array]) we should check for any edge cases and probably add some tests.</issue_description>

• Closes Generic method type parameter support #212

Comments on the Issue (you are Copilot in this section)

• Fixes Generic method type parameter support #212