Replace alacritty with xdg-terminal-exec in the waybar

[pomartel]

Right-clicking on the waybar cpu icon opens a Alacritty. I changed it to use the user's preferred terminal instead.

Since right clicking the waybar Omarchy logo already opens a terminal, we could also remove the right click action for the cpu icon.

[neheb]

I could be wrong but I think the intention here is to provide a fallback for systems that don't support ghostty.

[pomartel]

xdg-terminal-exec opens alacritty if it is set as the preferred terminal app.

[dhh]

As others have mentioned, this is essentially a backup for when Ghostty won't run on a system. It's not meant to be a general purpose launcher for the terminal. We already have that on Super + Return 👍