Add commit-pinned release packages omarchy and omarchy-settings

Stable-track counterparts of the -dev packages. Source is pinned to a
single shared upstream commit with a real sha256 (pacman 7 validates
checksums on commit-pinned git sources), versioned per the attached-rcN
convention so vercmp orders rc1 < rc2 < final. Seeded at 4.0.0rc1 from
the quattro tip because no upstream 4.x tag exists yet and the packaging
requires the quattro tree (v3.8.x has no shell/ or etc/).

Both packages stay off the fast ring: RCs publish to edge only; stable
receives finals via bin/repo migrate.

pkgbuilds/omarchy-settings/omarchy-settings.install

@@ -0,0 +1,39 @@
+_etc_overrides_apply() {
+  echo "Applying Omarchy etc-overrides..."
+
+  # Ensure parent dirs exist. cups-browsed may not be installed yet during ISO
+  # bootstrap; do not create /etc/cups/cups-browsed.conf before the package is
+  # installed or pacman will preserve its packaged file as a noisy .pacnew.
+  install -d /etc/plymouth /etc/security /etc/skel
+
+  # NOTE: these cp -f's are intentionally destructive on every install/upgrade.
+  # Users who customize /etc/os-release, /etc/plymouth/plymouthd.conf (theme
+  # switch), /etc/cups/cups-browsed.conf, /etc/nsswitch.conf,
+  # /etc/security/faillock.conf, or /etc/skel/.bashrc WILL have their changes
+  # reset to Omarchy defaults each time omarchy-settings is upgraded. This is
+  # the trade-off of routing upstream-owned paths through etc-overrides instead
+  # of pacman backup=().
+  rm -f /etc/os-release
+  cp -f /usr/share/omarchy/etc-overrides/os-release              /etc/os-release
+  cp -f /usr/share/omarchy/etc-overrides/security-faillock.conf  /etc/security/faillock.conf
+  cp -f /usr/share/omarchy/etc-overrides/nsswitch.conf           /etc/nsswitch.conf
+  if [[ -f /etc/cups/cups-browsed.conf ]]; then
+    install -d /etc/cups
+    cp -f /usr/share/omarchy/etc-overrides/cups-cups-browsed.conf /etc/cups/cups-browsed.conf
+  fi
+  cp -f /usr/share/omarchy/etc-overrides/plymouth-plymouthd.conf /etc/plymouth/plymouthd.conf
+  cp -f /usr/share/omarchy/etc-overrides/dot.bashrc              /etc/skel/.bashrc
+  chmod 0644 /etc/os-release /etc/security/faillock.conf /etc/nsswitch.conf \
+             /etc/plymouth/plymouthd.conf /etc/skel/.bashrc
+  if [[ -f /etc/cups/cups-browsed.conf ]]; then
+    chmod 0644 /etc/cups/cups-browsed.conf
+  fi
+}
+
+post_install() {
+  _etc_overrides_apply
+}
+
+post_upgrade() {
+  _etc_overrides_apply
+}