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

feat(emailer): add Postmark and Resend providers

backend/Modules/Contents/Features/CreateAlbum.cs

@@ -0,0 +1,75 @@
+using Hutopy.Infrastructure.Security;
+using Hutopy.Modules.Contents.Data;
+
+namespace Hutopy.Modules.Contents.Features;
+
+[PublicAPI]
+public record CreateAlbumRequest(
+    Guid AlbumId,
+    string Title,
+    string? Description = null);
+
+[PublicAPI]
+public record CreateAlbumResponse(
+    Guid AlbumId);
+
+[PublicAPI]
+public sealed class CreateAlbumRequestValidator : Validator<CreateAlbumRequest>
+{
+    public CreateAlbumRequestValidator()
+    {
+        RuleFor(x => x.AlbumId)
+            .NotNull()
+            .NotEmpty();
+
+        RuleFor(x => x.Title)
+            .NotNull()
+            .NotEmpty()
+            .MaximumLength(255);
+
+        RuleFor(x => x.Description)
+            .MaximumLength(1000);
+    }
+}
+
+[PublicAPI]
+public class CreateAlbumHandler(
+    ContentsDbContext context)
+    : Endpoint<CreateAlbumRequest, CreateAlbumResponse>
+{
+    public override void Configure()
+    {
+        Post("/api/albums");
+        Options(o => o.WithTags("Albums"));
+    }
+
+    public override async Task HandleAsync(
+        CreateAlbumRequest request,
+        CancellationToken ct)
+    {
+        // Check if an album with the same ID already exists
+        var existingAlbum = await context
+            .Albums
+            .AnyAsync(a => a.Id == request.AlbumId, ct);
+
+        if (existingAlbum)
+        {
+            await SendErrorsAsync(409, ct);
+            return;
+        }
+
+        var album = new Album
+        {
+            Id = request.AlbumId,
+            CreatedBy = User.GetUserId(),
+            Title = request.Title
+        };
+
+        context.Albums.Add(album);
+        await context.SaveChangesAsync(ct);
+
+        await SendOkAsync(
+            new CreateAlbumResponse(album.Id),
+            ct);
+    }
+}