Add keybind action copy_url_to_clipboard

[mitchellh]

Discussion: #4616

We should introduce a new keybind action copy_url_to_clipboard that copies the URL below the mouse to the clipboard. This should work with both normal detection and OSC8.

With the new performable: binding prefix, its easy to make this only have an affect while there is a link present.

[AlexJuca]

@mitchellh Where do existing key bind actions live?

Also, what do you mean by: "it should work both for normal detection and OSC8"?

Additionally, Would I be correct to assume that this can all be done without touching the native parts of Ghostty?

[mitchellh]

@mitchellh Where do existing key bind actions live?

src/input/Binding.zig

Also, what do you mean by: "it should work both for normal detection and OSC8"?

Regex-matched and esc-seq created links. Basically, all link types supported by Ghostty.

Additionally, Would I be correct to assume that this can all be done without touching the native parts of Ghostty?

Yes, I believe so.

[AlexJuca]

@mitchellh Here is an MR that correctly implements the required functionality.

#4678