feat: enhance frontend UI — command palette, admin redesign, API coverage

Types + API:
- Add User, TemplatePreview, QueueCustomField types
- Add getUsers, getTemplates, createTemplate, updateTemplate,
  previewTemplate, updateQueue, updateLifecycle, updateCustomField API functions

UI:
- Command palette: keyboard-first navigation with fuzzy ticket search
- Admin: comprehensive redesign with tab-based layout (Queues, Lifecycles,
  Scrips, Custom Fields, Templates, Users)
- Ticket list: improved inbox-style rows with quick actions
- Ticket detail: enhanced conversation thread and properties sidebar
- App shell: sidebar visual refinement with active indicator bar
- Theme toggle: smoother transitions

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

web/package.json

@@ -3,9 +3,10 @@
   "version": "0.1.0",
   "private": true,
   "scripts": {
-    "dev": "next dev",
+    "dev": "next dev --webpack -H 127.0.0.1 --port 3100",
+    "dev:prod": "next build && next start -H 127.0.0.1 --port 3100",
     "build": "next build",
-    "start": "next start",
+    "start": "next start -H 127.0.0.1 --port 3100",
     "lint": "eslint"
   },
   "dependencies": {