auth: show email verified banner on login page after verification

- Append ?verified=true to callbackURL in verification link
- Login page reads query param and shows green success banner
  when user lands after email verification

src/lib/server/email-verification.ts

@@ -1,11 +1,11 @@
-import { BASE_URL } from '$env/static/private';
+import { BETTER_AUTH_URL } from '$env/static/private';
 import { sendMail } from './resend';
 
 export async function sendVerificationEmail(options: {
 	email: string;
 	token: string;
 }) {
-	const verificationUrl = `${BASE_URL}/api/auth/verify-email?token=${options.token}&callbackURL=/login`;
+	const verificationUrl = `${BETTER_AUTH_URL}/api/auth/verify-email?token=${options.token}&callbackURL=/login?verified=true`;
 
 	await sendMail({
 		to: options.email,

src/routes/login/+page.svelte

@@ -1,11 +1,14 @@
 <script lang="ts">
 	import { authClient } from '$lib/auth-client';
+	import { page } from '$app/state';
 	import Window from '$lib/components/containers/Window.svelte';
 	let email = $state('');
 	let password = $state('');
 	let error = $state('');
 	let rememberMe = $state(false);
 
+	let verified = $derived(page.url.searchParams.get('verified') === 'true');
+
 	async function handleSubmit() {
 		const { data, error: authError } = await authClient.signIn.email({
 			email,
@@ -24,6 +27,13 @@
 
 <Window>
 	<div>
+		{#if verified}
+			<div
+				class="mb-4 rounded-lg border border-green-200 bg-green-50 p-4 text-green-700"
+			>
+				Your email has been verified. You can now log in.
+			</div>
+		{/if}
 		{#if error}
 			<span class="text-red-600">{error}</span>
 		{/if}