Load KefinTweaks scripts which don't require login/admin before users login

scripts/watchlist.js

@@ -4616,11 +4616,13 @@ In the Custom Tabs plugin, add a new tab with the following HTML content:
 	}
 
 	// Initialize monitoring to remove watched items from watchlist (playback + manual)
-	function initializePlaybackMonitoring() {
+	async function initializePlaybackMonitoring() {
 		if (playbackMonitorInitialized) {
 			return;
 		}
 
+		await window.userHelper.waitForLogin();
+
 		const maxRetries = 10;
 		let retries = 0;
 		// Use WebSocket to listen for UserDataChanged messages instead of intercepting fetch