Use user ID for umami identify when authenticated

src/routes/+page.svelte

@@ -174,7 +174,8 @@
 		if (!browser) return;
 		anonymousId = getOrCreateAnonymousId();
 		if ((window as any).umami) {
-			(window as any).umami.identify(anonymousId);
+			// Use user id if logged in, otherwise use anonymous id
+			(window as any).umami.identify(user ? user.id : anonymousId);
 		}
 		const statsKey = `bibdle-stats-submitted-${dailyVerse.date}`;
 		statsSubmitted = localStorage.getItem(statsKey) === "true";
@@ -264,7 +265,7 @@
 			(async () => {
 				try {
 					const response = await fetch(
-						`/api/submit-completion?anonymousId=${anonymousId}&date=${dailyVerse.date}`,
+						`/api/submit-completion?anonymousId=${user ? user.id : anonymousId}&date=${dailyVerse.date}`,
 					);
 					const result = await response.json();
 					console.log("Stats response:", result);
@@ -294,7 +295,7 @@
 		async function submitStats() {
 			try {
 				const payload = {
-					anonymousId,
+					anonymousId: user ? user.id : anonymousId,
 					date: dailyVerse.date,
 					guessCount: guesses.length,
 				};
@@ -455,7 +456,7 @@
 			<div class="mt-4 flex flex-col items-center gap-3">
 				<div class="flex gap-3">
 					<a 
-						href="/stats?anonymousId={anonymousId}"
+						href="/stats?{user ? `userId=${user.id}` : `anonymousId=${anonymousId}`}"
 						class="inline-flex items-center px-4 py-2 bg-amber-600 text-white rounded-lg hover:bg-amber-700 transition-colors text-sm font-medium shadow-md"
 					>
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