feat: add wlsunset home-manager module for Wayland night light

Replace the manual wlsunset package + commented exec-once with a proper
home-manager services.wlsunset module tied to hyprland-session.target.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

dotfiles/config/hypr/hyprland.conf

@@ -599,5 +599,3 @@ exec-once = ~/.config/hypr/scripts/workspace-history.sh
 exec-once = wl-paste --type text --watch cliphist store
 exec-once = wl-paste --type image --watch cliphist store
 
-# Night light (optional - comment out if not needed)
-# exec-once = wlsunset -l 37.7 -L -122.4

nixos/desktop.nix

@@ -5,6 +5,7 @@ makeEnable config "myModules.desktop" true {
     ./fonts.nix
     ./hyprland.nix
     ./keyd.nix
+    ./wlsunset.nix
   ];
 
   assertions = [

nixos/hyprland.nix

@@ -22,7 +22,6 @@ makeEnable config "myModules.hyprland" true {
     grim           # Screenshot utility
     slurp          # Region selection
     swappy         # Screenshot annotation
-    wlsunset       # Night light / blue light filter
     nwg-displays   # GUI monitor arrangement
 
     # hy3 plugin from flake (properly built against matching Hyprland)

nixos/wlsunset.nix

@@ -0,0 +1,17 @@
+{ config, pkgs, lib, makeEnable, ... }:
+makeEnable config "myModules.wlsunset" true {
+  home-manager.sharedModules = [
+    {
+      services.wlsunset = {
+        enable = true;
+        latitude = 37.7;
+        longitude = -122.4;
+        temperature = {
+          day = 6500;
+          night = 4000;
+        };
+        systemdTarget = "hyprland-session.target";
+      };
+    }
+  ];
+}