♻️ consolidate nix configs

nix/modules/coredns/default.nix

@@ -0,0 +1,45 @@
+{ config, lib, ... }:
+with lib;
+
+let cfg = config.walkah.coredns;
+in
+{
+  options.walkah.coredns = {
+    enable = mkEnableOption "";
+    addr = mkOption {
+      type = types.str;
+      default = "0.0.0.0";
+      example = "192.168.6.1";
+    };
+  };
+
+  config = mkIf cfg.enable {
+    services.coredns = {
+      enable = true;
+      config = ''
+        . {
+          bind 127.0.0.1
+          bind ${cfg.addr}
+          prometheus ${cfg.addr}:9153
+          log
+          errors
+          cache
+          dnssec
+          forward . tls://1.1.1.1 tls://1.0.0.1 {
+            tls_servername cloudflare-dns.com
+          }
+        }
+
+        walkah.lab {
+          bind ${cfg.addr}
+          file ${./walkah.lab.zone}
+        }
+      '';
+    };
+
+    networking = {
+      nameservers = [ "127.0.0.1" ];
+      search = [ "walkah.lab" ];
+    };
+  };
+}