Automatic fallback to Alacritty for legacy GPUs when install Omarchy

[yaroslavrick]

Description:

Closes #3581

Context

Ghostty requires modern GPU acceleration (OpenGL/Vulkan) which is often unstable or missing on legacy hardware, specifically pre-GCN AMD GPUs using the radeon kernel driver. On these systems, Ghostty may crash immediately, rendering the system difficult to use post-install.

ghostty_bug.mp4

Changes

This PR implements an automatic detection and fallback mechanism:

Detection:

Added bin/omarchy-detect-legacy-gpu which checks for the presence of the radeon driver in /sys/class/drm. This script is designed to be extensible for other legacy drivers in the future.

Fallback:

Added install/config/hardware/legacy-gpu-terminal.sh which runs during installation. If legacy hardware is detected, it calls omarchy-install-terminal alacritty to set Alacritty as the default terminal.

Package:

Added alacritty to install/omarchy-base.packages to ensure the fallback terminal is always available.

Hook:

Wired up the new configuration script in install/config/all.sh

Verification

• Verified that the fallback script correctly returns legacy driver name (radeon in this case):

• Verified that the fallback script works with modern GPU (in Arch linux):

[yaroslavrick]

Because of I do not have not legacy laptop, it worth to run this script on modern machine to check:

for d in /sys/class/drm/card*/device/driver; do basename $(readlink -f $d); done

[dhh]

Let's just inline the check here. I don't think this has any general utility outside this use case at the moment.

Also, it should do a full swap of Ghostty for Alacritty. Which will involve setting it as the default terminal etc. Not just installing it.

[yaroslavrick]

Thank you for the suggestion!

Fixed