Implement Startup Snapshot

[HalidOdat]

This Pull Request fixes/closes #1372 .

This is WIP implementation of startup snapshots, it needs a lot of work.

TODO:

• Figure out optimal snapshot file format.
• Implement full serialization
• Implement full deserialization
• Implement snapshot checksum
• Implement snapshot versioning
• Move under feature flag

[github-actions]

Test262 conformance changes

Test result	main count	PR count	difference
Total	94,842	94,842	0
Passed	74,691	74,691	0
Ignored	18,812	18,812	0
Failed	1,339	1,339	0
Panics	0	0	0
Conformance	78.75%	78.75%	0.00%

[codecov]

Codecov Report

Merging #3041 (fd9f5b3) into main (a9a2e1b) will decrease coverage by 0.88%.
The diff coverage is 0.00%.

@@            Coverage Diff             @@
##             main    #3041      +/-   ##
==========================================
- Coverage   50.42%   49.54%   -0.88%     
==========================================
  Files         444      450       +6     
  Lines       45877    46689     +812     
==========================================
  Hits        23132    23132              
- Misses      22745    23557     +812     

Impacted Files	Coverage Δ
boa_cli/src/debug/mod.rs	0.00% <0.00%> (ø)
boa_cli/src/debug/snapshot.rs	0.00% <0.00%> (ø)
boa_cli/src/main.rs	0.56% <0.00%> (-0.05%)	⬇️
boa_engine/src/builtins/iterable/mod.rs	65.60% <0.00%> (-4.95%)	⬇️
boa_engine/src/builtins/uri/mod.rs	21.11% <0.00%> (-0.73%)	⬇️
boa_engine/src/context/intrinsics.rs	76.55% <0.00%> (-21.61%)	⬇️
boa_engine/src/context/mod.rs	55.31% <0.00%> (-2.25%)	⬇️
boa_engine/src/environments/compile.rs	77.77% <0.00%> (-7.08%)	⬇️
...e/src/environments/runtime/declarative/function.rs	61.01% <0.00%> (-18.99%)	⬇️
...ine/src/environments/runtime/declarative/global.rs	76.92% <0.00%> (-23.08%)	⬇️
... and 29 more