refactor(auth): cleanup auth module and streamline the registration flow

backend/Modules/Identity/Handlers/ResendVerification.cs

@@ -0,0 +1,58 @@
+using Hutopy.Modules.Identity.Data;
+using Hutopy.Modules.Identity.Services;
+
+namespace Hutopy.Modules.Identity.Handlers;
+
+[PublicAPI]
+public record ResendVerificationRequest(
+    string Email);
+
+[PublicAPI]
+public record ResendVerificationResponse(
+    string Message);
+
+[PublicAPI]
+public class ResendVerificationHandler(
+    EmailVerificationService emailWriter,
+    UserManager userManager)
+    : Endpoint<ResendVerificationRequest, ResendVerificationResponse>
+{
+    public override void Configure()
+    {
+        AllowAnonymous();
+        Post("/api/users/resend-verification");
+        Options(o => o.WithTags("Users"));
+    }
+
+    public override async Task HandleAsync(
+        ResendVerificationRequest request,
+        CancellationToken ct)
+    {
+        // Find a user by email
+        User? user = await userManager.FindByEmailAsync(request.Email);
+        if (user is null)
+        {
+            // Don't reveal that the user doesn't exist
+            await SendOkAsync(
+                new ResendVerificationResponse(
+                    "If your email exists in our system, a verification link has been sent."),
+                ct);
+            return;
+        }
+
+        // Check if the email is already confirmed
+        if (user.EmailConfirmed)
+        {
+            await SendOkAsync(
+                new ResendVerificationResponse("Your email is already verified. You can log in."),
+                ct);
+            return;
+        }
+
+        await emailWriter.SendVerificationEmailAsync(user);
+
+        await SendOkAsync(
+            new ResendVerificationResponse("If your email exists in our system, a verification link has been sent."),
+            ct);
+    }
+}