feat: Add "win" as an alias for both lwin and rwin

[Miitto]

Adds an alias called win for both lwin and rwin, for some parity with other modifiers, and convenience.

For any keybind that uses win, it duplicates it and makes on for lwin and one for rwin.

- commands: ["focus --direction left"]
  bindings: ["win+left"]
- commands: ["focus --direction right"]
  bindings: ["win+right"]

Will be parsed and stored in the ParsedConfig as if you had used:

- commands: ["focus --direction left"]
  bindings: ["lwin+left", "rwin+left"]
- commands: ["focus --direction right"]
  bindings: ["lwin+right", "rwin+right"]

[lars-berger]

I think the ideal here would be to instead have a Key enum and implement conversion methods from strings and from vkeys. That way we could convert from strings when creating the hashmap in keybindings_by_trigger_key, and then from the u16 vkey when the keypress comes in. We could then fully avoid duplicating the keybinding and also handle any other vkeys that don't line up nicely

#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
pub enum Key {
    A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W, X, Y, Z,
    D0, D1, D2, D3, D4, D5, D6, D7, D8, D9,
    Numpad0, Numpad1, Numpad2, Numpad3, Numpad4, Numpad5, Numpad6, Numpad7, Numpad8, Numpad9,
    F1, F2, F3, F4, F5, F6, F7, F8, F9, F10, F11, F12,
    F13, F14, F15, F16, F17, F18, F19, F20, F21, F22, F23, F24,
    Shift, LShift, RShift,
    Control, LControl, RControl,
    Alt, LAlt, RAlt,
    Win, LWin, RWin, // !! win is a separate member of the enum
    Space, Escape, Back, Tab, Enter,
    Left, Right, Up, Down,
    NumLock, ScrollLock, CapsLock,
    PageUp, PageDown, Insert, Delete, End, Home,
    PrintScreen,
    Multiply, Add, Subtract, Decimal, Divide,
    VolumeUp, VolumeDown, VolumeMute,
    MediaNextTrack, MediaPrevTrack, MediaStop, MediaPlayPause,
    OemSemicolon, OemQuestion, OemTilde, OemOpenBrackets,
    OemPipe, OemCloseBrackets, OemQuotes, OemPlus,
    OemComma, OemMinus, OemPeriod,
    Custom(u16) // !!
}

impl Key {
    pub fn from_str(key: &str) -> Option<Self> {
        match key.to_lowercase().as_str() {
            "a" => Some(Key::A),
            "b" => Some(Key::B),
            // ...
            _ => {
              // Check if the key exists on the current keyboard layout.
              let utf16_key = key.encode_utf16().next()?;
             // ...
             Some(Key::Custom(xx))
        }
    }

    pub fn from_vk(vk: u16) -> Option<Self> {
        match VIRTUAL_KEY(vk) {
            VK_A => Some(Key::A),
            VK_B => Some(Key::B),
            // ...
        }
    }
}