Fix issue with some terminal that might not properly support kitty

[PitiBouchon]

Reason

On terminal like Alacritty, Rioterm and Ghostty that "kind of support" kitty protocol (but maybe not perfectly ?), the side-effect of supports_keyboard_enhancement seems to cause some issues when some characters are printed on linux (cf. https://github.com/nushell/nushell/issues/13570#issuecomment-2956045122)

Using kitty_protocol_available only once when the struct is initialized would solve the issue and I think is a bit better to do.

Alternative

use a a static std::sync::Once instead ?