clan: add temporary patched coredns service

Needed for IPv6 support, and to set the host names
in the auth zone.

clanServices/coredns/flake-module.nix

@@ -0,0 +1,18 @@
+{ ... }:
+let
+  module = ./default.nix;
+in
+{
+  clan.modules = {
+    "@rpqt/coredns" = module;
+  };
+  # perSystem =
+  #   { ... }:
+  #   {
+  #     clan.nixosTests.coredns = {
+  #       imports = [ ./tests/vm/default.nix ];
+
+  #       clan.modules."@rpqt/coredns" = module;
+  #     };
+  #   };
+}