feat: add signalr hub and github workflow

TetrisClone.WebApi/Model/Piece.cs

@@ -0,0 +1,14 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading.Tasks;
+
+namespace TetrisClone.WebApi.Model
+{
+    public class Piece
+    {
+        public int X { get; set; }
+        public int Y { get; set; }
+        public PieceType Type { get; set; }
+    }
+}