Gate empty-packet log under debug, add packet exclusion list

- Change empty packet log from log.Warn to log.Debug so it only
  shows when DebugMessages is enabled
- Add PacketDebugExclusions config (List<string>) to suppress
  specific packet types like KeepAlive, Ping from packet debug output
- Check exclusion in both LogIncomingPacket and LogOutgoingPacket
- Add ConfigComments resource entry for the new setting

MinecraftClient/Resources/ConfigComments/ConfigComments.Designer.cs

@@ -1541,6 +1541,15 @@ namespace MinecraftClient {
             }
         }
         
+        /// <summary>
+        ///   Looks up a localized string similar to Packet types to exclude from packet debug logs, e.g. [&quot;KeepAlive&quot;, &quot;Ping&quot;]..
+        /// </summary>
+        internal static string Logging_PacketDebugExclusions {
+            get {
+                return ResourceManager.GetString("Logging.PacketDebugExclusions", resourceCulture);
+            }
+        }
+        
         /// <summary>
         ///   Looks up a localized string similar to Show error messages..
         /// </summary>

MinecraftClient/Resources/ConfigComments/ConfigComments.resx

@@ -629,6 +629,9 @@ Want to upgrade to a newer version? See https://github.com/MCCTeam/Minecraft-Con
   <data name="Logging.PacketDebugMessages" xml:space="preserve">
     <value>Show low-level packet debug logs.</value>
   </data>
+  <data name="Logging.PacketDebugExclusions" xml:space="preserve">
+    <value>Packet types to exclude from packet debug logs, e.g. ["KeepAlive", "Ping"].</value>
+  </data>
   <data name="Logging.ErrorMessages" xml:space="preserve">
     <value>Show error messages.</value>
   </data>