many fixes and improvements - rework for modules/ and common/

feat(emailer): add Postmark and Resend providers

backend/Modules/Identity/Handlers/ChangeFullname.cs

@@ -0,0 +1,44 @@
+using Hutopy.Infrastructure.Security;
+using Hutopy.Modules.Identity.Data;
+
+namespace Hutopy.Modules.Identity.Handlers;
+
+[PublicAPI]
+public record ChangeFullnameRequest(
+    string? Firstname,
+    string? Lastname);
+
+[PublicAPI]
+public class ChangeFullnameHandler(
+    UserManager userManager)
+    : Endpoint<ChangeFullnameRequest>
+{
+    public override void Configure()
+    {
+        Post("/api/users/fullname");
+        Options(o => o.WithTags("Users"));
+    }
+
+    public override async Task HandleAsync(
+        ChangeFullnameRequest request,
+        CancellationToken ct)
+    {
+        var user = await userManager.FindByIdAsync(HttpContext.User.GetUserId().ToString());
+
+        if (user is null)
+        {
+            await SendNotFoundAsync(ct);
+            return;
+        }
+
+        user.Firstname = request.Firstname;
+        user.Lastname = request.Lastname;
+
+        var result = await userManager.UpdateAsync(user);
+
+        if (result.Succeeded)
+            await SendOkAsync(ct);
+        else
+            await SendUnauthorizedAsync(ct);
+    }
+}