fix(bot): make proxy/log blacklists work properly with threads

Handling of both blacklists was inconsistent when dealing with threads:
- proxy blacklist of root channel blacklists all threads
- log blacklist of root channel _did not apply_ to threads
- couldn't proxy blacklist threads while leaving root channel proxyable

This change fixes the inconsistencies:
- proxy _and_ log blacklist of root channel affects all threads
- now able to individually proxy/log blacklist threads, with root
  channel unaffected

PluralKit.Bot/Services/LogChannelService.cs

@@ -63,11 +63,12 @@ public class LogChannelService
             return null;
 
         var guildId = proxiedMessage.Guild ?? trigger.GuildId.Value;
+        var rootChannel = await _cache.GetRootChannel(trigger.ChannelId);
 
         // get log channel info from the database
         var guild = await _repo.GetGuild(guildId);
         var logChannelId = guild.LogChannel;
-        var isBlacklisted = guild.LogBlacklist.Any(x => x == trigger.ChannelId);
+        var isBlacklisted = guild.LogBlacklist.Any(x => x == trigger.ChannelId || x == rootChannel.Id);
 
         // if (ctx.SystemId == null ||
         // removed the above, there shouldn't be a way to get to this code path if you don't have a system registered