MangoWC and Scroll Greeter Support for NixOS (#1647)

* add mangowc greeter to nix.

i am going to be suprised if this only needed this line

* point mangowc to mango

there is no way this works

* mango flake detection and maybe scroll support

* " "

* no mango flake dependency

* mango dependency remove too

i have got to add "parenthesis" to stuff more

* Final De-dependification of MangoWC

it works without the flake YES

* mangowc -> mango pt 1

* mangowc -> mango pt 2

necessary evil. will break inital greetd confs but works after change

* Preserve Compatibility

quickshell/Modules/Greetd/assets/dms-greeter

@@ -14,7 +14,7 @@ dms-greeter - DankMaterialShell greeter launcher
 Usage: dms-greeter --command COMPOSITOR [OPTIONS]
 
 Required:
-    --command COMPOSITOR    Compositor to use (niri, hyprland, sway, scroll, mangowc, or labwc)
+    --command COMPOSITOR    Compositor to use (niri, hyprland, sway, scroll, mango, or labwc)
 
 Options:
     -C, --config PATH       Custom compositor config file
@@ -30,7 +30,7 @@ Examples:
     dms-greeter --command sway -p /home/user/.config/quickshell/custom-dms
     dms-greeter --command scroll -p /home/user/.config/quickshell/custom-dms
     dms-greeter --command niri --cache-dir /tmp/dmsgreeter
-    dms-greeter --command mangowc
+    dms-greeter --command mango
     dms-greeter --command labwc
 EOF
 }
@@ -253,7 +253,7 @@ SCROLL_EOF
         fi
         ;;
 
-    mangowc)
+    mango|mangowc)
         if [[ -n "$COMPOSITOR_CONFIG" ]]; then
             exec mango -c "$COMPOSITOR_CONFIG" -s "$QS_CMD && mmsg -d quit"
         else
@@ -263,7 +263,7 @@ SCROLL_EOF
 
     *)
         echo "Error: Unsupported compositor: $COMPOSITOR" >&2
-        echo "Supported compositors: niri, hyprland, sway, scroll, mangowc, labwc" >&2
+        echo "Supported compositors: niri, hyprland, sway, scroll, mango, labwc" >&2
         exit 1
         ;;
 esac