feat: Implement AsyncEventLoopExecutor to lay foundation

[scottmarchant]

Summary

Implement AsyncEventLoopExecutor that forms the basis of operations for NIOAsyncRuntime

Details

• d7f5ff7 feat: Add AsyncEventLoopExecutor that forms the foundation for creating AsyncEventLoop.

Usage Examples

• Spin up an executor and drive scheduled work:

let executor = AsyncEventLoopExecutor(loopID: UUID())
executor.enqueue { print("run on loop") }
let jobID = executor.schedule(after: .milliseconds(10), job: { print("delayed") }, failFn: { _ in })
await executor.run()
executor.cancelScheduledJob(withID: jobID)

Testing Performed

Tests coverage provided in tests ported from NIOPosix: #6.

The changes have also been tested in real-world application by running GraphManager and QuantumProjectManager in the browser to migrate database schemas, connect with our server, and pull data from a real user account.

PR Dependencies

#3

Overview of all changes

All planned changes can be viewed together in #2

[CrownedPhoenix]

Did this start as copy-pasta from a NIO implementation and then get pruned down to rip out unavailable dependencies?

[scottmarchant]

Did this start as copy-pasta from a NIO implementation and then get pruned down to rip out unavailable dependencies?

@CrownedPhoenix No, this started out as a new implementation. It actually started out really simple, just had the actor serial guard. But grew rather complex with all the different edge cases required for unit test parity. At some point, I wouldn't mind revisiting it and trying to split apart some of the responsibilities. It is admittedly pretty hard to follow right now.