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

feat(emailer): add Postmark and Resend providers

backend/Infrastructure/BlobStorage/Contracts/IBlobStorage.cs

@@ -0,0 +1,32 @@
+namespace Hutopy.Infrastructure.BlobStorage.Contracts;
+
+public interface IBlobStorage
+{
+    /// <summary>
+    /// Upload a file to blob storage.
+    /// </summary>
+    /// <param name="containerName">The name of the container where the file is stored.</param>
+    /// <param name="blobName">The blob name (path within the container, include the file name).</param>
+    /// <param name="stream"></param>
+    /// <param name="contentType">The content type.</param>
+    /// <param name="ct">The cancellation token</param>
+    /// <returns></returns>
+    Task<string> UploadFileAsync(
+        string containerName, 
+        string blobName, 
+        Stream stream,
+        string contentType,
+        CancellationToken ct = default);
+
+    /// <summary>
+    /// Download a file to blob storage.
+    /// </summary>
+    /// <param name="blobName">The blob name (path within the container).</param>
+    /// <param name="containerName">The name of the container where the file is stored. (users)</param>
+    /// <param name="ct">The cancellation token for the request</param>
+    /// <returns></returns>
+    Task<MemoryStream> DownloadFileAsync(
+        string containerName,
+        string blobName,
+        CancellationToken ct = default);
+}