Refactor proxy handling code

- Move reaction handlers to the ReactionAdded event instead of
  ProxyService
- Split tag matching off into ProxyTagParser
- Split autoproxy matching off into Autoproxier
- General cleanup and simplification

PluralKit.Bot/Handlers/MessageDeleted.cs

@@ -1,31 +1,39 @@
-using System.Collections.Generic;
 using System.Linq;
 using System.Threading.Tasks;
 
 using DSharpPlus.EventArgs;
 
-using Sentry;
+using PluralKit.Core;
+
+using Serilog;
 
 namespace PluralKit.Bot
 {
     // Double duty :)
     public class MessageDeleted: IEventHandler<MessageDeleteEventArgs>, IEventHandler<MessageBulkDeleteEventArgs>
     {
-        private readonly ProxyService _proxy;
+        private readonly IDataStore _data;
+        private readonly ILogger _logger;
 
-        public MessageDeleted(ProxyService proxy)
+        public MessageDeleted(IDataStore data, ILogger logger)
         {
-            _proxy = proxy;
+            _data = data;
+            _logger = logger.ForContext<MessageDeleted>();
         }
         
-        public Task Handle(MessageDeleteEventArgs evt)
+        public async Task Handle(MessageDeleteEventArgs evt)
         {
-            return _proxy.HandleMessageDeletedAsync(evt);
+            // Delete deleted webhook messages from the data store
+            // (if we don't know whether it's a webhook, delete it just to be safe)
+            if (!evt.Message.WebhookMessage) return;
+            await _data.DeleteMessage(evt.Message.Id);
         }
 
-        public Task Handle(MessageBulkDeleteEventArgs evt)
+        public async Task Handle(MessageBulkDeleteEventArgs evt)
         {
-            return _proxy.HandleMessageBulkDeleteAsync(evt);
+            // Same as above, but bulk
+            _logger.Information("Bulk deleting {Count} messages in channel {Channel}", evt.Messages.Count, evt.Channel.Id);
+            await _data.DeleteMessagesBulk(evt.Messages.Select(m => m.Id).ToList());
         }
     }
 }