Protocol changes for 1.21.20: ServerboundDiagnosticsPacket & 1.21.2: ServerboundLoadingScreenPacket

[xxAROX]

Add ServerboundDiagnosticsPacket into bedrock/1.21.20/protocol.json

[xxAROX]

And ServerboundLoadingScreenPacket also I think - 1.21.2

[xxAROX]

Reproduce it with a relay on pmmp latest

[xxAROX]

Fix on serverbound event:

player.on("serverbound", ({name, params}, des) => {
        if ([312, 315].includes(name)) {
            des.canceled = true;
            // @ts-ignore
            player.upstream.sendBuffer(des.fullBuffer);
        }
    });