Redesign CLI executor to avoid spin looping when idle

[jedel1043]

The design of our current event loop on the CLI has a couple of warts; one of them being that if there are any async jobs or timeout jobs but not any other type of job on the queue, it will start spin looping, consuming a lot of CPU resources.

This PR completely redesigns our event loop to use smol and cooperative async tasks to push the jobs forward, which avoids spin looping by delegating pauses and timeouts to smol (effectively delegating those to the OS, and OS sleeping = 0% CPU usage). This redesign also modularizes the way jobs are ran; instead of having a big loop that goes through all of the job queues at once, it extracts the running logic of each job queue into independent async tasks

[github-actions]

Test262 conformance changes

Test result	main count	PR count	difference
Total	52,963	52,963	0
Passed	50,073	50,073	0
Ignored	2,072	2,072	0
Failed	818	818	0
Panics	0	0	0
Conformance	94.54%	94.54%	0.00%

Tested main commit: 3f04847b88529e2c62f13d2b36ed4149df507211
Tested PR commit: fbf2312d53205ff810d4f0161f3f30ba22e56117
Compare commits: 3f04847...fbf2312

[codecov]

Codecov Report

❌ Patch coverage is 10.56911% with 110 lines in your changes missing coverage. Please review.
✅ Project coverage is 59.50%. Comparing base (6ddc2b4) to head (5ed2f6d).
⚠️ Report is 894 commits behind head on main.

Files with missing lines	Patch %	Lines
cli/src/executor.rs	0.00%	88 Missing ⚠️
core/engine/src/job.rs	40.00%	18 Missing ⚠️
cli/src/main.rs	0.00%	2 Missing ⚠️
core/engine/src/builtins/atomics/futex.rs	33.33%	2 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##             main    #4994       +/-   ##
===========================================
+ Coverage   47.24%   59.50%   +12.25%     
===========================================
  Files         476      580      +104     
  Lines       46892    63301    +16409     
===========================================
+ Hits        22154    37666    +15512     
- Misses      24738    25635      +897     

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[github-actions]

Test262 conformance changes

Test result	main count	PR count	difference
Total	52,963	52,963	0
Passed	50,079	50,079	0
Ignored	2,072	2,072	0
Failed	812	812	0
Panics	0	0	0
Conformance	94.55%	94.55%	0.00%

Tested main commit: c9aaad16b19aa2cadf72838fe8acc1043013023c
Tested PR commit: 5ed2f6d6bcd6e1b2a2e91a60963e3881dab794bc
Compare commits: c9aaad1...5ed2f6d

[hansl]

Isn't this just:

Suggested change

	#[cfg(debug_assertions)]
	{
	let callback = self.0.take();
	assert!(
	callback.is_some(),
	"setting a callback on an already used cancellation token"
	);
	}
	debug_assert!(self.0.take().is_none(), "setting a callback on an already used cancellation token");

Also, I think the logic is wrong, you want to make sure it's None before setting it.

[jedel1043]

Nah, it needs to check if it is Some, otherwise the token has already been used and the Cell has a None on its place