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

feat(emailer): add Postmark and Resend providers

backend/Modules/Messaging/Handlers/DeleteMessage.cs

@@ -0,0 +1,52 @@
+using Hutopy.Infrastructure.Security;
+using Hutopy.Modules.Messaging.Data;
+
+namespace Hutopy.Modules.Messaging.Handlers;
+
+public record DeleteMessageRequest(Guid MessageId);
+
+internal sealed class DeleteMessageRequestValidator
+    : Validator<DeleteMessageRequest>
+{
+    public DeleteMessageRequestValidator()
+    {
+        RuleFor(r => r.MessageId)
+            .NotNull().WithMessage("You must specify a MessageId")
+            .NotEmpty().WithMessage("You must specify a non-empty MessageId");
+    }
+}
+
+public class DeleteMessage(
+    MessagingDbContext context)
+    : Endpoint<DeleteMessageRequest>
+{
+    public override void Configure()
+    {
+        Delete("/api/messages/{MessageId}");
+        Options(o => o.WithTags("Messages"));
+    }
+
+    public override async Task HandleAsync(
+        DeleteMessageRequest req,
+        CancellationToken ct)
+    {
+        var message = await context.Messages.FirstOrDefaultAsync(x => x.Id == req.MessageId, ct);
+
+        if (message is null)
+        {
+            await SendNotFoundAsync(ct);
+            return;
+        }
+        
+        var userId = HttpContext.User.GetUserId();
+        if (message.CreatedBy != userId)
+        {
+            await SendForbiddenAsync(ct);
+            return;
+        }
+        
+        context.Messages.Remove(message);
+
+        await context.SaveChangesAsync(ct);
+    }
+}