src: use native CopyArrayBufferBytes for webstream buffer copy

[Renegade334]

Use the V8 API path for these, which performs its own bounds handling.

I'm not seeing any performance delta, but we may as well not reinvent the wheel.

[Renegade334]

SharedArrayBuffers could never make it down this path, as canCopyArrayBuffer() uses ArrayBuffer primordials which throw on SharedArrayBuffers.

[codecov]

Codecov Report

❌ Patch coverage is 56.00000% with 11 lines in your changes missing coverage. Please review.
✅ Project coverage is 90.37%. Comparing base (f71d644) to head (6b117f7).
⚠️ Report is 27 commits behind head on main.

Files with missing lines	Patch %	Lines
src/node_buffer.cc	56.00%	8 Missing and 3 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #66400      +/-   ##
==========================================
+ Coverage   90.36%   90.37%   +0.01%     
==========================================
  Files         792      792              
  Lines      275564   275562       -2     
  Branches    52832    52829       -3     
==========================================
+ Hits       249016   249048      +32     
+ Misses      16965    16920      -45     
- Partials     9583     9594      +11     

Files with missing lines	Coverage Δ
src/node_buffer.cc	70.43% <56.00%> (+0.03%)	⬆️

... and 30 files with indirect coverage changes

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[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/78095/