refactor: consume computer-use packages from NUR (#375)

* refactor: consume computer-use packages from NUR

* fix: expose flake inputs to package overlays

Package overlays are imported from two places with different argument
shapes: outputs/default.nix passes a set containing `inputs`, while
modules/base/overlays.nix passes the NixOS module args, where genSpecialArgs
spreads each flake input as a top-level argument. The new NUR-backed
overlays read `inputs.nur-ryan4yin`, so evaluation failed on the module
path. Also expose the whole flake input set as `inputs` in genSpecialArgs.

* chore: bump nur-ryan4yin input

Update the locked nur-packages revision to the current main (nixpkgs
26.05, unused packages removed).

outputs/default.nix

@@ -21,7 +21,15 @@ let
     in
     inputs
     // {
-      inherit mylib myvars pkgs-stable;
+      # The spread above exposes each flake input as a top-level argument.
+      # Also expose the whole set as `inputs`, which the package overlays
+      # (`overlays/*.nix`) receive via `import ../overlays args`.
+      inherit
+        inputs
+        mylib
+        myvars
+        pkgs-stable
+        ;
 
       # use unstable branch for some packages to get the latest updates
       # pkgs-unstable = import inputs.nixpkgs-unstable {