v2.7.0

Enhancements:

• Added AsyncEnumerable<T> allocation-free async iterators (requires C# 7.3 or newer).
• Added allocation-free async Linq extensions for AsyncEnumerable<T>.
• Added optional ContentionStrategy to AsyncReaderWriterLock.
• Added Promise.ParallelForEachAsync APIs to consume AsyncEnumerable<T> and IAsyncEnumerable<T> in parallel.
• Added new Progress APIs.
• Added Promise.Finally overloads accepting Func<Promise> delegates to support DisposeAsync.
• Added PromiseYielder.{WaitForUpdate, WaitForLateUpdate} APIs.

Fixes:

• Fixed an exception in Unity after exiting playmode with reload domain disabled.
• Fixed AsyncLocal<T> in Promise.Parallel* body.
• Fixed an error log when clearing the object pool in a rare case.

Optimizations:

• Improved performance of async Promise functions in netstandard2.1 and Unity 2021.2 or newer.

Deprecated:

• Deprecated old progress APIs (Deferred.ReportProgress, Promise.Progress, Promise.AwaitWithProgress). Replaced with new Progress APIs.