fix(manacore-web): fix login redirect flow

- Root +page.svelte: use authStore instead of data.session (always undefined)
  → after email verification auto-sign-in, redirects to /home not /login
- (auth)/+layout.svelte: remove racing $effect, keep only onMount redirect check
  → no more double goto() race condition after login
- login/+page.svelte: successRedirect /dashboard → /home (consistent with root)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

apps/manacore/apps/web/src/routes/(auth)/+layout.svelte

@@ -8,21 +8,11 @@
 
 	let { children }: { children: Snippet } = $props();
 	let isDark = $derived(theme.isDark);
-	let hasCheckedAuth = $state(false);
-
-	// Check auth status on mount
+	// If user is already authenticated when visiting auth pages, redirect to home
 	onMount(async () => {
 		await authStore.initialize();
-		hasCheckedAuth = true;
 		if (authStore.isAuthenticated) {
-			goto('/dashboard');
-		}
-	});
-
-	// Also react to auth state changes (e.g., after successful login)
-	$effect(() => {
-		if (hasCheckedAuth && authStore.isAuthenticated) {
-			goto('/dashboard');
+			goto('/home');
 		}
 	});
 </script>

apps/manacore/apps/web/src/routes/(auth)/login/+page.svelte

@@ -38,7 +38,7 @@
 	onVerifyBackupCode={(code) => authStore.verifyBackupCode(code)}
 	onSendMagicLink={(email) => authStore.sendMagicLink(email)}
 	{goto}
-	successRedirect="/dashboard"
+	successRedirect="/home"
 	registerPath="/register"
 	forgotPasswordPath="/forgot-password"
 	lightBackground="#f3f4f6"

apps/manacore/apps/web/src/routes/+page.svelte

@@ -1,13 +1,14 @@
 <script lang="ts">
 	import { goto } from '$app/navigation';
+	import { onMount } from 'svelte';
+	import { authStore } from '$lib/stores/auth.svelte';
 
-	let { data } = $props();
-
-	$effect(() => {
-		if (!data.session) {
-			goto('/login');
-		} else {
+	onMount(async () => {
+		await authStore.initialize();
+		if (authStore.isAuthenticated) {
 			goto('/home');
+		} else {
+			goto('/login');
 		}
 	});
 </script>