Eliminate ByteBuf copy in chunk translator

[ByteExceptionM]

The chunk translator was copying the ByteBuf into a byte array and then wrapping it again into a new buffer for the packet. That means every chunk that gets sent briefly exists twice in memory. Removed that extra copy by passing the buffer directly to the packet via retainedSlice(). This cuts memory usage per chunk in half during translation and reduces GC pressure, especially noticeable when players are loading lots of chunks at once.

[Copilot]

Pull request overview

This PR aims to reduce chunk translation overhead by removing an intermediate byte[] copy when building the Bedrock LevelChunkPacket, instead passing a Netty ByteBuf slice directly.

Changes:

• Removes copying ByteBuf contents into a byte[] and wrapping it again for the packet payload.
• Sends LevelChunkPacket with byteBuf.retainedSlice() as the data payload.
• Switches the output buffer allocation from ByteBufAllocator.DEFAULT.ioBuffer(size) to Unpooled.buffer(size).

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[valaphee]

LGTM

[onebeastchris]

Thank you!