move options to separate modules, set up mkDocs generation

modules/global/home.nix

@@ -1,5 +1,7 @@
 { inputs, self, ... }: {
   flake.homeModules.global = { lib, config, pkgs, ... }: {
+    imports = [ self.homeModules.globalOptions ];
+
     nix.gc = lib.mkIf (!config.features.applications.cli.nh.enable) {
       automatic = true;
       persistent = true;