Ship zram tuning as a vendor drop-in

pacman checks file conflicts during transaction prepare, so the --overwrite
entry added alongside /etc/systemd/zram-generator.conf never got to run: the
copy of omarchy-update-system-pkgs driving the upgrade is the one already on
disk. Every machine carrying archinstall's copy aborted the transaction.

zram-generator.conf(5) reserves /etc for the local admin and has vendors ship
snippets under /usr/lib/systemd/zram-generator.conf.d/, where drop-ins outrank
the main config file. Nothing collides, and the tuning wins whether or not
archinstall's file is still around.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01LjeyQZsNBxqyYy9z8KaKm7

migrations/1785013000.sh

@@ -0,0 +1,28 @@
+echo "Move zram tuning to a vendor drop-in"
+
+zram_conf="${OMARCHY_ZRAM_CONF:-/etc/systemd/zram-generator.conf}"
+
+# The tuning ships as /usr/lib/systemd/zram-generator.conf.d/90-omarchy.conf.
+# Drop-ins outrank the main config file, so a leftover /etc copy decides nothing
+# and only implies /etc is where zram gets configured.
+
+[[ -f $zram_conf ]] || exit 0
+
+# Package-owned copies go away with their package on upgrade.
+pacman -Qo "$zram_conf" &>/dev/null && exit 0
+
+# archinstall writes exactly a [zram0] section with one compression-algorithm
+# line. Anything else is a deliberate local override. grep exits 1 on a config
+# that sets nothing at all, which omarchy-migrate's -e would take as a failed
+# migration and block every migration behind this one.
+settings=$(grep -vE '^[[:space:]]*([#;]|$)' "$zram_conf" | tr -d '[:space:]') || true
+
+if [[ -z $settings || $settings =~ ^\[zram0\]compression-algorithm=[[:alnum:]-]+$ ]]; then
+  # A refused sudo just leaves the file for next time; tidying is not worth
+  # failing the migration chain over.
+  sudo rm -f "$zram_conf" || true
+else
+  echo "Keeping $zram_conf; it has local edits."
+  echo "Omarchy's drop-in overrides it. Move your changes to"
+  echo "/etc/systemd/zram-generator.conf.d/99-local.conf to keep them in effect."
+fi