refactor: overlay

overlays/default.nix

@@ -14,15 +14,17 @@
         )
       '';
 
-      sing-box.__output.version.__assign = "unstable-2024-08-16";
-      sing-box.__output.src.__assign = final.fetchFromGitHub {
+      sing-box.__assign = infuse prev.sing-box {
+        version.__assign = "unstable-2024-08-16";
+        src.__assign = final.fetchFromGitHub {
           owner = "PuerNya";
           repo = "sing-box";
           rev = "067c81a73e1fb7b6edbc58e6b06b8b943fa6c40a";
           hash = "sha256-03mkClYVAfAatfYJ1OuM1OvABj/fgbseqK8jPbBtI8g=";
         };
-      sing-box.__output.vendorHash.__assign = "sha256-ZWFZkVRtybQAK9oZRIMBGeDfxXTV7kzXwNSbkvslMFk=";
-      sing-box.__output.postInstall.__assign = "";
+        vendorHash.__assign = "sha256-ZWFZkVRtybQAK9oZRIMBGeDfxXTV7kzXwNSbkvslMFk=";
+        postInstall.__assign = "";
+      };
     };
 
   # this allows us to access specific version of nixpkgs