README.md updates

Author: ixetanet

README.md

@@ -56,6 +56,17 @@ https://localhost:PORT/__/auth/handler      (Development)
 
 The `/__/auth/handler` endpoint is automatically provided by Xams (`app.AddFirebaseAuthProxy()`), implementing [Firebase's redirect best practice Option 3](https://firebase.google.com/docs/auth/web/redirect-best-practices) - proxying auth through your backend. This is **required** for custom domains with Google OAuth.
 
+## Firebase Email Templates
+
+Configure the Firebase email template action URL to redirect to your Xams application:
+
+1. Navigate to **Authentication → Templates** in the Firebase console
+2. Select an email template and click **Edit Template**
+3. Click **Customize action URL**
+4. Set the URL to your application's action handler (e.g., `https://localhost:3000/__/auth/action`)
+
+This URL handles email verification, password reset, and other Firebase authentication actions.
+
 ## Test Your Configuration
 
 In Program.cs, with useAuth = true, navigate to the admin dashboard to verify Firebase authentication is working: