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.Database/AspNetUsersId.sql

@@ -0,0 +1,3 @@
+-- This is so I don't have to remember the type used in the dbo.AspNetUsers table for the Id column.
+CREATE TYPE [dbo].[AspNetUsersId]
+	FROM NVARCHAR(450) NOT NULL;