expose TransferQueue utils

[zhabuye]

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[Copilot]

Pull Request Overview

This PR exposes TransferQueue utilities by adding four new utility modules to the experimental transfer queue package. The utilities include enums and role definitions, ZeroMQ message handling, serialization with msgpack/pickle for PyTorch tensors and TensorDict objects, and a package initialization file.

Key changes:

• Adds core utilities for transfer queue roles and production status enums
• Implements ZeroMQ utilities for distributed messaging and communication
• Provides advanced serialization utilities for PyTorch tensors and TensorDict objects

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

File	Description
verl/experimental/transfer_queue/utils/init.py	Package initialization with copyright headers
verl/experimental/transfer_queue/utils/utils.py	Core enums, Ray placement group utilities, and tensor field extraction
verl/experimental/transfer_queue/utils/zmq_utils.py	ZeroMQ message types, server info, and socket creation utilities
verl/experimental/transfer_queue/utils/serial_utils.py	Msgpack encoder/decoder for PyTorch tensors and TensorDict serialization

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[Copilot]

The type annotation Optional[str | None] is redundant. Optional[str] already includes None, so this should be simplified to Optional[str].

Suggested change

	receiver_id: Optional[str | None] = None,
	receiver_id: Optional[str] = None,

[0oshowero0]

If not used now, we can delete this file