feat(webhooks): init, add service/models, add JSON to patch objects

PluralKit.Core/Database/Repository/ModelRepository.cs

@@ -6,10 +6,12 @@ namespace PluralKit.Core
     {
         private readonly ILogger _logger;
         private readonly IDatabase _db;
-        public ModelRepository(ILogger logger, IDatabase db)
+        private readonly DispatchService _dispatch;
+        public ModelRepository(ILogger logger, IDatabase db, DispatchService dispatch)
         {
             _logger = logger.ForContext<ModelRepository>();
             _db = db;
+            _dispatch = dispatch;
         }
     }
 }