Use the durable Home reset boundary

tests/quickshell/settings-commit-reset-contract.sh

@@ -19,6 +19,7 @@ set -euo pipefail
 
 repo_dir="$(cd "$(dirname "${BASH_SOURCE[0]}")/../.." && pwd)"
 harness="$repo_dir/config/dot/quickshell/settings-system-harness.qml"
+system_settings="$repo_dir/config/dot/quickshell/services/SystemSettings.qml"
 
 # Preferences are committed to $XDG_CONFIG_HOME, and the Home store lives under
 # $XDG_STATE_HOME. Both are isolated so this contract cannot touch the real
@@ -31,6 +32,12 @@ fail() {
     exit 1
 }
 
+rg -Fq 'HomePreferences.resetHomeDefaults();' "$system_settings" \
+    || fail 'restoreDefaults does not use the durable Home reset boundary'
+if rg -q 'HomePreferences\.(favorites|initialized)\s*=' "$system_settings"; then
+    fail 'restoreDefaults mutates Home aliases instead of using resetHomeDefaults'
+fi
+
 qs_for_harness() {
     XDG_CONFIG_HOME="$config_home" XDG_STATE_HOME="$state_home" qs -p "$harness" "$@"
 }