ref(nix)!: reorganize overlays

fix the issue where exported modules can't find exported packages

nix/overlays/default.nix

@@ -1,4 +1,9 @@
-{ inputs, lib, ... }:
+{
+  inputs,
+  lib,
+  self,
+  ...
+}:
 
 {
 
@@ -35,10 +40,8 @@
           disko
           ;
       };
-    in
-    {
 
-      default = lib.composeManyExtensions [
+      reexports = [
         externPackages
 
         inputs.nur.overlays.default
@@ -46,7 +49,14 @@
 
         inputs.hoot.overlays.default
       ];
-
+    in
+    {
+      default = lib.composeManyExtensions (
+        reexports
+        # Scope my overlay
+        ++ [ (final: prev: { myPkgs = self.overlays.packages final prev; }) ]
+      );
+      reexports = lib.composeManyExtensions reexports;
     };
 
 }