Ghostty's GTK4 window construction made every launch sluggish on neogaia's
integrated graphics (~440 ms to map a window), which a head-to-head
comparison against Alacritty confirmed. Alacritty's lightweight OpenGL
renderer opens fast on the iGPU, so it becomes the terminal on Super+Return.
The choice stays reversible per host, so a capable host such as zeus could
adopt Ghostty later.