feat: Introduce arbitrary batched tokens

[raphaelrobert]

No description provided.

[Copilot]

Pull Request Overview

This PR introduces arbitrary batched tokens functionality, refactoring both the public and private token protocols and updating associated tests, benchmarks, and documentation. Key changes include:

• Refactored client APIs to use new static token request constructors (e.g. TokenRequest::new) and removed redundant client structs.
• Added new modules for arbitrary batched tokens with corresponding test files and server/client implementations.
• Updated dependency versions and improved inline documentation in test utilities and token server/client modules.

Reviewed Changes

Copilot reviewed 26 out of 26 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
tests/*	Refactored test vectors and evaluation functions to use new API calls and async processing for token generation.
src/public_tokens/*	Updated client APIs and modified create_keypair to return only the public key alongside adjusted type aliases.
src/private_tokens/*	Refactored client implementation to use static constructors and improved derive attributes for token types.
src/arbitrary_batched_tokens/*	Introduced modules and types for arbitrary batched tokens, including custom (de)serialization logic.
benches/*	Updated benchmark code to use the new API patterns and constructor methods.
Cargo.toml	Bumped dependency versions and added support for test utilities.

Comments suppressed due to low confidence (1)

src/public_tokens/server.rs:107

• The return type of create_keypair has been changed from KeyPair to PublicKey; please update the function comment and any related documentation to clearly reflect this new behavior.

Ok(key_pair.pk)