Expose nvim's "winblend" floating window option

[simonmclean]

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• Yes

Is your feature request related to a problem? Please describe.

I use several plugins which make use of floating windows (Telescope, FTerm, Mason, Lazy, Triptych) and I'd like to unify their appearance as much as possible, including the use of subtle transparency. Some of the plugins listed already support this, while others don't. So I'm hoping Mason can be added to that list :)

Describe the solution you'd like

This commit in my fork does the job: simonmclean@e279b96

It exposes it via settings.ui.winblend and defaults to 0 (no transparency)

Describe potential alternatives you've considered

No response

Additional context

No response