Adds Blazor Web App standard login

WatchLog/Data/DatabaseModels/Shared/LinkTableSharedUser.cs

@@ -0,0 +1,21 @@
+using System.ComponentModel.DataAnnotations.Schema;
+using Microsoft.EntityFrameworkCore;
+
+namespace WatchLog.Data
+{
+    [PrimaryKey(nameof(SharedListId), nameof(UserId))]
+    public class LinkTableSharedUser
+    {
+        // --- Foreign Keys ---
+        public int SharedListId { get; set; }
+        public string? UserId { get; set; }
+
+
+        // --- Navigation Properties ---
+        [ForeignKey(nameof(SharedListId))]
+        public virtual SharedList SharedList { get; set; } = null!;
+
+        [ForeignKey(nameof(UserId))]
+        public virtual ApplicationUser User { get; set; } = null!;
+    }
+}