This replaces the use of our custom `Ghostty.KeyEquivalent` with
the SwiftUI `KeyboardShortcut` type. This is a more standard way to
represent keyboard shortcuts and lets us more tightly integrate with
SwiftUI/AppKit when necessary over our custom type.
Note that not all Ghostty triggers can be represented as
KeyboardShortcut values because macOS itself does not support
binding keys such as function keys (e.g. F1-F12) to KeyboardShortcuts.
This isn't an issue since all input also passes through a lower level
libghostty API which can handle all key events, we just can't show these
keyboard shortcuts on things like the menu bar. This was already true
before this commit.
Fixes#2848
The proper way to convert a unicode scalar in Swift is to use the
`String` initializer that takes a `UnicodeScalar` as an argument. We
were converting a number to a string before, which is incorrect.
This was recently introduced a few days ago. Unfortunately, this doesn't
work as expected. The "function" modifier is not actually the fn key
but used by macOS to represent a variety of "functional" key presses.
This breaks other bindings such as #2411.
I can't find a source on the internet that reliably tells me how we
can detect fn key presses, but I do find a number of sources that tell
us we can't.
Nit picky change, but the OptionSet class (which NSEvent.ModifierFlags
is an instance of) has an API for incrementally setting values without
needing to create an array.
