Major config overhaul: use custom modules, setup for multi-host config, and less boilerplate

modules/system/security/blocklist/default.nix

@@ -0,0 +1,18 @@
+{ config, lib, inputs, ... }:
+
+let
+  blocklist = builtins.readFile "${inputs.blocklist-hosts}/alternates/gambling-porn/hosts";
+  cfg = config.systemSettings.security.blocklist;
+in {
+  options = {
+    systemSettings.security.blocklist = {
+      enable = lib.mkEnableOption "Enable basic host blocking for bad websites";
+    };
+  };
+
+  config = lib.mkIf cfg.enable {
+    networking.extraHosts = ''
+      "${blocklist}"
+    '';
+  };
+}