Reorganize, shared entities from TypeScript SDK

https://github.com/cloudflare/cloudflare-typescript/blob/v4.4.1/src/resources/shared.ts

Cloudflare/Models/Identifier.cs

@@ -0,0 +1,15 @@
+namespace AMWD.Net.Api.Cloudflare
+{
+	/// <summary>
+	/// A Cloudflare identifier.
+	/// <see href="https://github.com/cloudflare/cloudflare-typescript/blob/v4.4.1/src/resources/shared.ts#L266">Source</see>
+	/// </summary>
+	public class Identifier
+	{
+		/// <summary>
+		/// Identifier.
+		/// </summary>
+		[JsonProperty("id")]
+		public string? Id { get; set; }
+	}
+}