more work on api & rename to Pilz.Net

Pilz.Net/Api/ApiResult.cs

@@ -0,0 +1,18 @@
+using System.Net;
+
+namespace Pilz.Net.Api;
+
+public record class ApiResult(
+    HttpStatusCode StatusCode,
+    ApiMessage? Message = null)
+{
+    public static ApiResult Ok()
+    {
+        return new(HttpStatusCode.OK);
+    }
+
+    public static ApiResult Ok(ApiMessage message)
+    {
+        return new(HttpStatusCode.OK, message);
+    }
+}