Add JS fallback render and remove asset query strings

Render basic cards if script.js fails to execute, show quick login icons by default, and avoid asset query params that can break on some static hosts.

Co-authored-by: Cursor <cursoragent@cursor.com>

script.js

@@ -1,6 +1,9 @@
 (() => {
   "use strict";
 
+  // Mark boot so index.html fallback won't run
+  globalThis.__LINKS_APP_BOOTED__ = true;
+
   const STORAGE_KEY = "links_home_v1";
   const THEME_KEY = "links_home_theme_v1";
   const AUTH_TOAST_ONCE_KEY = "links_home_auth_toast_once_v1";