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 9.35252% with 126 lines in your changes missing coverage. Please review.
✅ Project coverage is 59.76%. Comparing base (6ddc2b4) to head (b615a08).
⚠️ Report is 920 commits behind head on main.

Files with missing lines	Patch %	Lines
cli/src/executor.rs	0.00%	106 Missing ⚠️
core/engine/src/job.rs	41.37%	17 Missing ⚠️
core/engine/src/builtins/atomics/futex.rs	33.33%	2 Missing ⚠️
cli/src/main.rs	0.00%	1 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##             main    #4994       +/-   ##
===========================================
+ Coverage   47.24%   59.76%   +12.51%     
===========================================
  Files         476      589      +113     
  Lines       46892    63476    +16584     
===========================================
+ Hits        22154    37934    +15780     
- Misses      24738    25542      +804     

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[github-actions]

Test262 conformance changes

Test result	main count	PR count	difference
Total	52,963	52,963	0
Passed	50,732	50,732	0
Ignored	1,426	1,426	0
Failed	805	805	0
Panics	0	0	0
Conformance	95.79%	95.79%	0.00%

Tested main commit: 2437b6704c4315f6ec8f0766bf229fba23e0e61e
Tested PR commit: b615a08fa4faf680a8c8633b14c13c3ea3dbcca6
Compare commits: 2437b67...b615a08

[zhuzhu81998]

there are merge conflicts now?

and can we pls merge this asap. i have the tendency to forget closing the cli and my core 1 suffers for this 🥹

[nekevss]

LGTM

We should definitely merge this as soon as possible