angrr: add as NixOS and nix-darwin module

pulled in as flake because the darwin module has not been upstreamed
yet, anf or consistency sake take all modules from the same source then

common/angrr.nix

@@ -0,0 +1,12 @@
+{ config, ... }:
+{
+  services.angrr = {
+    enable = true;
+    period = "30d";
+    package = config.inputInjection.flake-inputs.angrr.packages.${config.nixpkgs.hostPlatform.system}.angrr;
+  };
+  # angrr.service runs before nix-gc.service by default
+  nix.gc.automatic = true;
+  # we use the nix-direnv built-in refresh funtionality, pulled in via home manager
+  programs.direnv.angrr.enable = false;
+}

common/default.nix

@@ -17,6 +17,7 @@ in
     ./upgrade-diff.nix
     ./guest.nix
     ./audio-sharing.nix
+    ./angrr.nix
   ];
 
   services.davfs2.enable = true;