basic summaries for all pair classes, create partial classes and condense models into a single file

LightlessSync/PlayerData/Pairs/PairLedger.cs

@@ -12,6 +12,9 @@ using Microsoft.Extensions.Logging;
 
 namespace LightlessSync.PlayerData.Pairs;
 
+/// <summary>
+///     keeps pair info for ui and reapplication
+/// </summary>
 public sealed class PairLedger : DisposableMediatorSubscriberBase
 {
     private readonly PairManager _pairManager;