feat(ui): redesign UI with Tailwind CSS, CodeMirror 6, and new layout

- Replace all hand-written CSS with Tailwind utility classes
- Upgrade CodeMirror 5 to CodeMirror 6 (scoped @codemirror/* packages)
- Redesign layout with responsive sidebar navigation using JSX/Mithril
- Flatten admin routes (e.g. /admin/presets -> /presets)
- Add "remember me" login option with 2-week persistent cookie
- Add delete confirmation dialogs across admin pages
- Upgrade esbuild from 0.21 to 0.27 and update browser targets
- Add Inter and Roboto Mono variable fonts with subset script

ui/autocomplete-compnent.ts

@@ -12,7 +12,7 @@ export default class Autocomplete {
   declare private selection: number;
   declare private container: HTMLElement;
 
-  public constructor(className: string, callback: AutocompleteCallback) {
+  public constructor(callback: AutocompleteCallback) {
     this.callback = callback;
     this.element = null;
     this.hideTimeout = null;
@@ -24,7 +24,8 @@ export default class Autocomplete {
     this.container.style.position = "absolute";
     this.container.style.display = "block";
     this.container.style.opacity = "0";
-    this.container.className = className;
+    this.container.className =
+      "absolute py-1 mt-2 rounded-md shadow-lg bg-white";
   }
 
   public attach(el: HTMLInputElement): void {
@@ -140,9 +141,10 @@ export default class Autocomplete {
       for (const [idx, suggestion] of suggestions.entries()) {
         const e = document.createElement("div");
         if (suggestion.tip) e.title = suggestion.tip;
-        e.classList.add("suggestion");
+        e.className =
+          "text-stone-700 block px-4 py-2 text-sm hover:bg-stone-100 hover:text-stone-900";
         if (idx === this.selection) {
-          e.classList.add("selected");
+          e.classList.add("bg-stone-100", "text-stone-900");
           selectedElement = e;
         }