First pass ext-encoding support

[dktapps]

Main changes:

• PacketSerializer is removed, all encode/decode methods previously in there are now static methods of CommonTypes
• DataPacket->decode() now accepts pmmp\encoding\ByteBufferReader
• DataPacket->encode() now accepts pmmp\encoding\ByteBufferWriter
• encode/decode functions all updated to use ext-encoding APIs

Questions/concerns/doubts:

• Not sure I like CommonTypes being static.
  • CommonTypes::writeString($out, $string) is more boilerplaty than $out->writeString($string)
  • While statics have benefit for the low-level APIs (since they prevent endian mistakes), CommonTypes doesn't need to be static.
  • It is consistent with the low-level API, I suppose...
  • Prevents overriding methods of PacketSerializer to customise packet decoding? but we were mostly gravitating towards final type classes having their own static ::read() and ->write() methods anyway...
• CommonTypes::writeOptional() looks nasty for objects and could be made prettier
• Generally, not convinced I made the right design choices for ext-encoding with the static API.

[Copilot]

Pull Request Overview

This PR implements first pass support for ext-encoding in the BedrockProtocol library. The primary purpose is to migrate from the previous PacketSerializer system to a new encoding system using pmmp/encoding library, which provides better performance and more structured data serialization.

Key changes include:

• Replace PacketSerializer with ByteBufferReader/ByteBufferWriter throughout the codebase
• Migrate to pmmp/encoding library for binary data operations (LE, VarInt, Byte, etc.)
• Introduce CommonTypes class to centralize common serialization operations

Reviewed Changes

Copilot reviewed 300 out of 356 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
Many entity type files	Update serialization methods to use new encoding system
Camera-related types	Migrate to ByteBufferReader/ByteBufferWriter
Biome generation types	Convert to pmmp/encoding format
Core packet types	Update to use CommonTypes and new buffer system
Serializer components	Replace PacketSerializer with CommonTypes utilities
Multiple packet classes	Implement new encoding/decoding with ByteBufferReader/Writer

---

_{Tip: Customize your code reviews with copilot-instructions.md. Create the file or learn how to get started.}