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]

Can you pick something besides the @mainactor now?

[scottmarchant]

@CrownedPhoenix Yep. That is what I'm doing here. @_AsyncEventLoopExecutor._IsolatingSerialEntryActor is equivalent to @MainActor, except that it forms it's own task pool separate from but similar to @MainActor.

[CrownedPhoenix]

Is reentrancy a problem here?

[scottmarchant]

Suggested change

	/// This is an actor designed to execute provided tasks in the order then enter the actor.
	/// This is an actor designed to execute provided tasks in the order they enter the actor.

[scottmarchant]

Suggested change

	// ^----- Ensures FIFO entry from nonisolated contexts
	// ^----- Ensures first-in entry from nonisolated contexts

[scottmarchant]

Suggested change

	/// We use this actor to make serialized FIFO entry
	/// We use this actor to make serialized first-in entry

[scottmarchant]

Suggested change

	// ^----- Ensures FIFO entry from nonisolated contexts
	// ^----- Ensures first-in entry from nonisolated contexts

[scottmarchant]

Suggested change

	// ^----- Ensures FIFO entry from nonisolated contexts
	// ^----- Ensures first-in entry from nonisolated contexts

[scottmarchant]

Suggested change

	// ^----- Ensures FIFO entry from nonisolated contexts
	// ^----- Ensures first-in entry from nonisolated contexts

[CrownedPhoenix]

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

[scottmarchant]

Suggested change

	// ^----- Ensures FIFO entry from nonisolated contexts
	// ^----- Ensures first-in entry from nonisolated contexts