Fix moderator status on broadcast

Authored-by: Tsubasahane <wozaiha@gmail.com>
Reviewed-on: #49
Co-authored-by: Tsubasa <tsubasa@noreply.git.lightless-sync.org>
Co-committed-by: Tsubasa <tsubasa@noreply.git.lightless-sync.org>

LightlessSyncServer/LightlessSyncServer/Hubs/LightlessHub.Groups.cs

@@ -1103,11 +1103,11 @@ public partial class LightlessHub
             return false;
         }
 
-        var (isOwner, _) = await TryValidateOwner(dto.GID).ConfigureAwait(false);
-        if (!isOwner)
+        var (isOwnerOrMod, _) = await TryValidateGroupModeratorOrOwner(dto.GID).ConfigureAwait(false);
+        if (!isOwnerOrMod)
         {
             _logger.LogCallWarning(LightlessHubLogger.Args("Unauthorized syncshell broadcast change", "User", UserUID, "GID", dto.GID));
-            await Clients.Caller.Client_ReceiveServerMessage(MessageSeverity.Error, "You must be the owner of the syncshell to broadcast it.");
+            await Clients.Caller.Client_ReceiveServerMessage(MessageSeverity.Error, "You must be the owner or moderator of the syncshell to broadcast it.");
             return false;
         }