fix: TypedArray offset and length not respected by TextDecoder

[zhuzhu81998]

Closes #4615 .
Started because #4637 was closed without merging by the author while it had conflicts due to changes on the main branch from #4670 (let me know in case it was not intended to be closed).

Compared to previous PRs on this matter including #4637, this PR avoids allocating unnecessarily.

[github-actions]

Test262 conformance changes

Test result	main count	PR count	difference
Total	52,862	52,862	0
Passed	49,505	49,505	0
Ignored	2,261	2,261	0
Failed	1,096	1,096	0
Panics	0	0	0
Conformance	93.65%	93.65%	0.00%

[codecov]

Codecov Report

❌ Patch coverage is 90.90909% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 57.22%. Comparing base (6ddc2b4) to head (a67feac).
⚠️ Report is 709 commits behind head on main.

Files with missing lines	Patch %	Lines
core/runtime/src/text/mod.rs	90.90%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4763      +/-   ##
==========================================
+ Coverage   47.24%   57.22%   +9.97%     
==========================================
  Files         476      553      +77     
  Lines       46892    60618   +13726     
==========================================
+ Hits        22154    34686   +12532     
- Misses      24738    25932    +1194     

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[zhuzhu81998]

hard to believe there is no test262 for this 🤔

[jedel1043]

That's because TextDecoder is not part of ECMA262; it is from a separate spec (https://encoding.spec.whatwg.org/). We kinda have tests for it in https://github.com/boa-dev/boa/tree/201418a5e1506ad098522be8d308bfbea80e495a/tests/wpt, but the repo download is kinda massive so we don't run it on our CI, and IIRC we would also need to enable the tests for TextDecoder

[jedel1043]

Cool, no idea why the original PR was closed but avoiding allocations seems better overall

[jedel1043]

Don't have any other comments then. We should try to fix the index inconsistency problem in a separate PR