add: obs and firefox, fix: desktop and greeter QoL

system/core/default.nix

@@ -2,10 +2,12 @@
   imports = [
     ./nix.nix
     ./boot.nix
-    ./uwsm.nix
     ./locale.nix
     ./network.nix
     ./fonts.nix
     ./sound.nix
+
+    ./uwsm.nix
+    ./regreet.nix
   ];
-}
+}

system/core/regreet.nix

@@ -0,0 +1,24 @@
+{
+  programs.regreet = {
+    enable = true;
+    settings = {
+      appearance = {
+        greeting_msg = "Welcome back!";
+      };
+      widget = {
+        clock = {
+          format = "%H:%M";
+          resolution = "100ms";
+          timezone = "Asia/Tokyo";
+          label_width = 150;
+        };
+      };
+      GTK = {
+        application_prefer_dark_theme = true;
+      };
+      background = {
+        path = "/usr/share/wallpaper/arknights-image-01.png";
+      };
+    };
+  };
+}