expose TransferQueueClient

[ji-huazhong]

What does this PR do?

As per title.

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[Copilot]

Pull Request Overview

This PR exposes TransferQueueClient classes by adding a complete client implementation for the transfer queue system. The primary purpose is to provide both synchronous and asynchronous client interfaces for interacting with transfer queue controllers and storage units via ZMQ messaging.

Key changes:

• Adds comprehensive client implementation with async operations (get_meta, put, get_data, clear)
• Provides synchronous wrapper for easier integration
• Implements dynamic socket management with automatic connection handling

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 3 comments.

File	Description
verl/experimental/transfer_queue/client.py	New file containing AsyncTransferQueueClient and TransferQueueClient classes with ZMQ-based communication
verl/experimental/transfer_queue/storage.py	Copyright year update from 2024 to 2025
verl/experimental/transfer_queue/init.py	Copyright year update from 2024 to 2025

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[Copilot]

Comment contains Chinese text. Should be translated to English: '# Return data and index information from this storage unit'

Suggested change

	# 返回该存储单元的数据和索引信息
	# Return data and index information from this storage unit

[Copilot]

Variable 'id' is undefined in this scope. Should use 'info.id' instead.

Suggested change

	raise ValueError(f"Invalid server info for {role} {id}")
	raise ValueError(f"Invalid server info for {role} {info.id}")

[Copilot]

[nitpick] The noqa comment 'UP007' suggests this is suppressing a ruff rule about Union syntax. Consider using the modern pipe syntax 'TransferQueueController | TransferQueueStorageSimpleUnit' instead of Union, or remove the noqa if the suppression is no longer needed.

Suggested change

	def process_zmq_server_info(handlers: dict[Any, Union[TransferQueueController, TransferQueueStorageSimpleUnit]]): # noqa: UP007
	def process_zmq_server_info(handlers: dict[Any, TransferQueueController | TransferQueueStorageSimpleUnit]):