fix injecting custom css and just change all the html pages instead.

Overlord-Server/public/assets/nav.js

@@ -6,12 +6,6 @@ import {
   subscribeUnread,
 } from "./notify-client.js";
 
-(function injectCustomCSS() {
-  const link = document.createElement("link");
-  link.rel = "stylesheet";
-  link.href = "/assets/custom.css";
-  document.head.appendChild(link);
-})();
 import { mountNav } from "./nav/template.js";
 import { createAdaptiveNavController } from "./nav/layout.js";
 import { applyUserRoleUI } from "./nav/role-ui.js";