Added ChangeLog

Added change log to track updates to the database, for easier pinging
from Syncer client.

FreeTubeSync/Model/Database/ChangeLog.cs

@@ -0,0 +1,9 @@
+namespace FreeTubeSync.Model.Database;
+
+public class ChangeLog
+{
+    public int Id { get; set; }
+    public string TableName { get; set; } = string.Empty;
+    public string ChangeType { get; set; } = string.Empty;
+    public DateTime ChangeTime { get; set; } = DateTime.MinValue;
+}