Modify boa_runtime's timers to use native timeout tracking and cancellation

[jedel1043]

This modifies the timer code in boa_runtime such that it uses the recently introduced CancellationToken.
It also removes usages of Rc<RefCell<>>, which are replaces by directly querying the context for a timeout tracker, making it possible to extract a &mut IntervalInnerState from it`.

Finally a couple of cleanups and renames here and there

[github-actions]

Test262 conformance changes

Test result	main count	PR count	difference
Total	52,963	52,963	0
Passed	50,735	50,735	0
Ignored	1,426	1,426	0
Failed	802	802	0
Panics	0	0	0
Conformance	95.79%	95.79%	0.00%

Tested main commit: f5e88de558e038f0ae675a012d59917a098f44b6
Tested PR commit: c8d01e1752c0224f027a5c44c3ef908fc1bb8888
Compare commits: f5e88de...c8d01e1

[codecov]

Codecov Report

❌ Patch coverage is 60.09615% with 83 lines in your changes missing coverage. Please review.
✅ Project coverage is 59.74%. Comparing base (6ddc2b4) to head (c8d01e1).
⚠️ Report is 925 commits behind head on main.

Files with missing lines	Patch %	Lines
core/engine/src/host_defined.rs	31.37%	35 Missing ⚠️
core/engine/src/job.rs	71.87%	27 Missing ⚠️
cli/src/executor.rs	0.00%	18 Missing ⚠️
core/engine/src/builtins/atomics/futex.rs	0.00%	2 Missing ⚠️
core/engine/src/context/mod.rs	83.33%	1 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##             main    #5289       +/-   ##
===========================================
+ Coverage   47.24%   59.74%   +12.49%     
===========================================
  Files         476      589      +113     
  Lines       46892    63591    +16699     
===========================================
+ Hits        22154    37992    +15838     
- Misses      24738    25599      +861     

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