fix(fetch): reject non-null window option in Request constructor

[HiteshShonak]

This Pull Request fixes/closes #5209.

It changes the following:

• Add window field to RequestInit and reject any non-null value with a TypeError.
• Add a consolidated regression test covering non-null values and confirming null is still accepted.

Testing:

cargo test -p boa_runtime request -- --nocapture

Spec reference: https://fetch.spec.whatwg.org/#dom-request

[Copilot]

Pull request overview

This PR updates Boa’s Fetch Request implementation to align with the Fetch Standard requirement that the window option must be null, and adds a regression test to ensure non-null values throw.

Changes:

• Extend RequestInit with a window field and throw a TypeError when window is non-null.
• Add a regression test that checks several non-null window values throw, while null is accepted.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
core/runtime/src/fetch/request.rs	Adds window to RequestInit and validates it during request construction.
core/runtime/src/fetch/tests/request.rs	Adds a regression test for Request constructor window option behavior.

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[github-actions]

Test262 conformance changes

Test result	main count	PR count	difference
Total	52,963	52,963	0
Passed	50,539	50,539	0
Ignored	1,426	1,426	0
Failed	998	998	0
Panics	2	2	0
Conformance	95.42%	95.42%	0.00%

Tested main commit: 58a24587890677d94618259dfaa5f257ab5ef9c9
Tested PR commit: 3e02909d88dc6e7ff1a519462743854cf8291f8f
Compare commits: 58a2458...3e02909

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 59.81%. Comparing base (6ddc2b4) to head (3e02909).
⚠️ Report is 913 commits behind head on main.

Additional details and impacted files

@@             Coverage Diff             @@
##             main    #5210       +/-   ##
===========================================
+ Coverage   47.24%   59.81%   +12.56%     
===========================================
  Files         476      582      +106     
  Lines       46892    63463    +16571     
===========================================
+ Hits        22154    37958    +15804     
- Misses      24738    25505      +767     

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