Add ProfileType enum and extension for URI scheme

Introduced the ProfileType enum with Http and Https values in the ReC.Domain.Constants namespace. Added ProfileTypeExtensions with a ToUriBuilderScheme method to convert enum values to their lowercase string representations for URI building.

src/ReC.Domain/Constants/ProfileType.cs

@@ -0,0 +1,12 @@
+namespace ReC.Domain.Constants;
+
+public enum ProfileType : byte
+{
+    Http = 1,
+    Https = 2
+}
+
+public static class ProfileTypeExtensions
+{
+    public static string ToUriBuilderScheme(this ProfileType profileType) => profileType.ToString().ToLower();
+}