stream: reject closed only after sink abort settles

[lazerg]

The writer's closed promise is materialized lazily, and the lazy derivation maps a stream in the 'errored' state straight to an already rejected promise. WritableStreamFinishErroring sets that state before it runs the sink's abort(), so a closed promise first observed inside that window comes back rejected while the sink is still tearing down. The spec only rejects it from WritableStreamRejectCloseAndClosedPromiseIfNeeded, in the reaction to the abort algorithm.

The closed records are now materialized as pending right before the abort algorithm runs, so the existing settle sites reject them at the point the spec does.

Fixes: #65726

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.07%. Comparing base (f9ab994) to head (b802059).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #65727      +/-   ##
==========================================
- Coverage   90.07%   90.07%   -0.01%     
==========================================
  Files         754      754              
  Lines      256395   256402       +7     
  Branches    48494    48508      +14     
==========================================
+ Hits       230947   230951       +4     
- Misses      16563    16576      +13     
+ Partials     8885     8875      -10     

Files with missing lines	Coverage Δ
lib/internal/webstreams/writablestream.js	93.51% <100.00%> (+0.03%)	⬆️

... and 29 files with indirect coverage changes

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[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/76858/