Set low urgency for immediate-feedback notifications (#5056)

Some users may choose to disable notification timeout for normal-level
notifications to ensure no notifications are missed when the user is
away from the screen. However, there are several Omarchy notifications
that only serve as an immediate feedback for a user action, such as
"Screensaver enabled" or "Editing config file foo.conf", for which
disabling the timeout is not desirable. This commit drops the urgency
level for such notification to low, allowing configuring a different
timeout value for them.

Notifications with an explicitly set timeout are excluded from this
commit.

bin/omarchy-toggle-nightlight

@@ -21,10 +21,10 @@ restart_nightlighted_waybar() {
 
 if [[ $CURRENT_TEMP == $OFF_TEMP ]]; then
   hyprctl hyprsunset temperature $ON_TEMP
-  notify-send "  Nightlight screen temperature"
+  notify-send -u low "  Nightlight screen temperature"
   restart_nightlighted_waybar
 else
   hyprctl hyprsunset temperature $OFF_TEMP
-  notify-send "   Daylight screen temperature"
+  notify-send -u low "   Daylight screen temperature"
   restart_nightlighted_waybar
 fi