UX/UI/perf pass: admin tabs, theme toggle, log polish, mod search, JAR cache

- Admin page split into tabs (Server/Players/Chat/Mods/Backups/Logs) with
  hash + localStorage persistence; inactive tabs no longer mount.
- Log viewer: level color-coding, search, level filter chips, auto-scroll
  toggle, copy button, visible-line count.
- Installed mods list: search field + side filter (all/both/server/client)
  with live count; public ModList gets skeleton + empty states and search.
- Theme toggle with no-flash inline init, localStorage + system preference.
- Layout: full OG / Twitter metadata, title template, keywords,
  dual-theme themeColor, metadataBase.
- lib/mods.ts: per-jar mtime+size parse cache (cold 6s -> warm ~45ms on
  /api/mods for the full mod list); cache eviction on mod removal.
- ChatBridge polling eased 3s -> 5s with 2s stale window.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

app/admin/page.tsx

@@ -1,14 +1,7 @@
 import { auth } from "@/lib/auth";
 import { redirect } from "next/navigation";
 import { Navbar } from "@/components/Navbar";
-import { ClientOnly } from "@/components/ClientOnly";
-import { ServerControls } from "@/components/ServerControls";
-import { Analytics } from "@/components/Analytics";
-import { PlayerManager } from "@/components/PlayerManager";
-import { ChatBridge } from "@/components/ChatBridge";
-import { ModManager } from "@/components/ModManager";
-import { BackupManager } from "@/components/BackupManager";
-import { LogViewer } from "@/components/LogViewer";
+import { AdminTabs } from "@/components/AdminTabs";
 import Link from "next/link";
 
 export default async function AdminPage() {
@@ -28,26 +21,18 @@ export default async function AdminPage() {
         </div>
       </div>
 
-      <ClientOnly>
-        <div className="max-w-5xl mx-auto px-3 py-4 sm:p-6 space-y-4 sm:space-y-6 w-full overflow-x-hidden">
-          <ServerControls />
-          <Analytics />
-          <PlayerManager />
-          <ChatBridge />
-          <ModManager />
-          <BackupManager />
-          <LogViewer />
+      <div className="max-w-5xl mx-auto px-3 py-4 sm:p-6 w-full overflow-x-hidden">
+        <AdminTabs />
 
-          <div className="text-center">
-            <Link
-              href="/"
-              className="text-sm text-muted-foreground hover:text-foreground transition"
-            >
-              Back to dashboard
-            </Link>
-          </div>
+        <div className="text-center mt-6">
+          <Link
+            href="/"
+            className="text-sm text-muted-foreground hover:text-foreground transition"
+          >
+            Back to dashboard
+          </Link>
         </div>
-      </ClientOnly>
+      </div>
     </>
   );
 }