Drop the kms hook when the proprietary NVIDIA driver handles early KMS (#6791)

* Drop the kms hook when the proprietary NVIDIA driver handles early KMS

install/hardware/nvidia.sh early-loads nvidia_drm (modeset=1) for early KMS,
but HOOKS still carried the kms hook, so autodetect pulled nouveau and
~100 MB of its GSP firmware into every initramfs for a driver that never
runs. On a Limine UKI setup that meant a 256 MB image where ~144 MB is
normal, doubled again by the fallback history on /boot.

Filter kms out of HOOKS when nvidia_drm is in MODULES (nvidia.conf sorts
before this drop-in) and every PCI display controller is NVIDIA. Hybrid
systems keep kms so the iGPU retains early KMS at the LUKS prompt.

Verified on an RTX 4090 (nvidia-open-dkms 610.57.04): UKI shrinks
256,183,296 -> 144,066,048 bytes, nouveau and its firmware gone, the
nvidia-utils GSP blobs and all four nvidia modules retained, Plymouth
still owns the LUKS prompt via nvidia_drm.

Fixes #6790

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

* Address review: quote literals, harden PCI detection, add shell tests

Quote fixed string literals in the [[ ]] comparisons per AGENTS.md, and
read the PCI tree through OMARCHY_PCI_DEVICES_PATH, the same seam
bin/omarchy-hw-nvidia already uses.

Require a positively identified NVIDIA display controller before dropping
kms: an empty or unreadable PCI tree previously counted as "no non-NVIDIA
GPU" and would have dropped the hook. Unexpected trees now keep kms.

Cover the conditional in test/shell.d/nvidia-kms-hook-test.sh: nvidia-only,
hybrid, no nvidia_drm, MODULES unset under set -u, audio-function-only,
empty tree, and a device directory missing its sysfs attributes.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

* Treat unreadable PCI devices as inconclusive and make the test hermetic

A device whose class/vendor attributes cannot be read could be another
GPU, so skipping it let a readable NVIDIA GPU beside it drop kms without
having verified the whole tree. Count it as a non-NVIDIA sighting so kms
stays, and cover the mixed case in the test.

The test also sourced the host's /etc/vconsole.conf under set -u, where a
valid KEYMAP-only file makes the XKBLAYOUT expansion fail in the subshell
and ties the result to the machine running it. Predefine XKBLAYOUT and
FILES before sourcing the config.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

* Rebuild existing initramfses once the kms hook no longer applies

The settings package deploys the new omarchy_hooks.conf conditional, but
nothing rebuilds the initramfs when only a mkinitcpio drop-in changes, so
existing NVIDIA-only installs would carry nouveau's ~100 MB of GSP
firmware until their next kernel update. Following the precedent of
1784476564, add a migration that rebuilds via limine-mkinitcpio — once
per machine, and only where evaluating the installed drop-ins shows the
conditional actually dropped kms, so hybrid machines, non-NVIDIA
machines, and user-edited configs are left alone.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

* Document the mid-sourcing MODULES caveat in the kms conditional

A later-sorting drop-in that resets MODULES outright (as
surface_device_modules.conf does) would strip nvidia_drm after kms was
already dropped. Every machine Omarchy writes such a file for is hybrid
Intel and keeps kms through the PCI scan, but that is worth stating so
the invariant is not broken by accident.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

---------

Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
Co-authored-by: David Heinemeier Hansson <david@hey.com>

migrations/1786605598.sh

@@ -0,0 +1,33 @@
+echo "Rebuild the initramfs so NVIDIA-only systems shed nouveau's unused GSP firmware"
+
+# omarchy_hooks.conf now filters the kms hook out of HOOKS when the proprietary
+# NVIDIA driver handles early KMS and NVIDIA owns every display controller
+# (#6790). The settings package deploys that conditional, but nothing rebuilds
+# the initramfs for a mkinitcpio drop-in change, so affected machines would
+# carry ~100 MB of dead nouveau firmware until their next kernel update.
+# Rebuild once, and only where the conditional actually changes the outcome:
+# evaluate the installed drop-ins the way mkinitcpio does and check that kms
+# dropped out. A user-edited omarchy_hooks.conf (pacman leaves the packaged
+# update as a .pacnew) keeps kms and correctly skips the rebuild.
+
+hooks_conf="${OMARCHY_MKINITCPIO_HOOKS_CONF:-/etc/mkinitcpio.conf.d/omarchy_hooks.conf}"
+nvidia_conf="${OMARCHY_MKINITCPIO_NVIDIA_CONF:-/etc/mkinitcpio.conf.d/nvidia.conf}"
+rebuild_marker="${OMARCHY_KMS_REBUILD_MARKER:-/var/lib/omarchy/migrations/1786605598}"
+
+omarchy-cmd-present limine-mkinitcpio || exit 0
+[[ -f $hooks_conf && -f $nvidia_conf ]] || exit 0
+
+# The rebuild is machine-wide, but migrations run once per user: a marker
+# records completion so another user's run does not repeat it, while a missing
+# marker still retries an interrupted rebuild.
+[[ ! -e $rebuild_marker ]] || exit 0
+
+# Source the drop-ins in mkinitcpio's order (nvidia.conf sorts first) and read
+# the HOOKS they produce. Skip conservatively if evaluation fails.
+hooks=$(bash -c 'source "$1" && source "$2" && echo " ${HOOKS[*]} "' -- "$nvidia_conf" "$hooks_conf") || exit 0
+
+[[ $hooks != *" kms "* ]] || exit 0
+
+echo "This machine no longer uses the kms hook; rebuilding the initramfs without nouveau"
+sudo limine-mkinitcpio
+sudo install -Dm644 /dev/null "$rebuild_marker"