Summary

Add sessions and transactions to the Async C Driver.

Motivation

Required for sessions, transactions, and causal-consistency specification compliance in the Async C Driver. Wraps the equivalent functionality in the Rust driver.

Acceptance Criteria

• Sessions can be started and ended.
• Transactions can be started, committed, and aborted.
• Behaviour matches the sessions and transactions specifications.
• Tests cover the added operations.

Out of Scope

withTransaction, from the transactions-convenient-api specification. That requires additional design for the Rust-to-C callback and is tracked as future work.