Replace custom socket implementation with SignalR.

Replace MSAL and custom cookie auth with Microsoft.Identity.EntityFramework
Also some UI redesign to accommodate different login experience.

Shogi.UI/Pages/Play/GamePiece.razor

@@ -0,0 +1,57 @@
+@using Shogi.Contracts.Types
+
+<div class="game-piece" title="@HtmlTitle" data-upsidedown="@(Piece?.Owner != Perspective)" data-owner="@Piece?.Owner.ToString()">
+	@switch (Piece?.WhichPiece)
+	{
+		case WhichPiece.Bishop:
+			<Bishop IsPromoted="@IsPromoted" />
+			break;
+		case WhichPiece.GoldGeneral:
+			<GoldGeneral />
+			break;
+		case WhichPiece.King:
+			<ChallengingKing />
+			break;
+		case WhichPiece.Knight:
+			<Knight IsPromoted="@IsPromoted" />
+			break;
+		case WhichPiece.Lance:
+			<Lance IsPromoted="@IsPromoted" />
+			break;
+		case WhichPiece.Pawn:
+			<Pawn IsPromoted="@IsPromoted" />
+			break;
+		case WhichPiece.Rook:
+			<Rook IsPromoted="@IsPromoted" />
+			break;
+		case WhichPiece.SilverGeneral:
+			<SilverGeneral IsPromoted="@IsPromoted" />
+			break;
+		default:
+			@*render nothing*@
+			break;
+	}
+</div>
+
+@code {
+	[Parameter]
+	public Contracts.Types.Piece? Piece { get; set; }
+
+	[Parameter]
+	public WhichPlayer Perspective { get; set; }
+
+	private bool IsPromoted => Piece != null && Piece.IsPromoted;
+
+	private string HtmlTitle => Piece?.WhichPiece switch
+	{
+		WhichPiece.Bishop => "Bishop",
+		WhichPiece.GoldGeneral => "Gold General",
+		WhichPiece.King => "King",
+		WhichPiece.Knight => "Knight",
+		WhichPiece.Lance => "Lance",
+		WhichPiece.Pawn => "Pawn",
+		WhichPiece.Rook => "Rook",
+		WhichPiece.SilverGeneral => "Silver General",
+		_ => string.Empty
+	};
+}