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

feat(emailer): add Postmark and Resend providers

backend/Infrastructure/Security/KnownClaims.cs

@@ -0,0 +1,7 @@
+namespace Hutopy.Infrastructure.Security;
+
+public static class KnownClaims
+{
+    public const string Alias = "alias";
+    public const string PortraitUrl = "portraitUrl";
+}