test(mock): make the delayed-abort test discriminate instead of asserting true

[pacocartones]

Problem

The first test in test/mock-delayed-abort.js ended with:

p.ok(true, 'No uncaught errors after delayed response')

That assertion is a tautology — it stays green no matter what the code under test does. The bare MockAgent.request path throws no uncaught error when a delayed reply is delivered after an abort, so the test passed even against a fully-broken guard. It documented an intent it never actually enforced: that a mocked reply delivered after the request was aborted must not still be pushed to the handler.

What this hardens

The post-abort guards live in lib/mock/mock-utils.js (the timer-clear on abort plus the two if (aborted) return guards in handleReply). To prove the test now discriminates, I reverted those three guards and re-ran:

variant	test 1 (this one)
real code	passes
guards reverted	fails

Previously, test 1 passed in both variants.

The change

The delayed-abort test now wraps the dispatched handler in a DecoratorHandler subclass that records any onResponseStart / onResponseData / onResponseEnd delivered after onResponseError, and asserts none occur:

p.strictEqual(deliveredAfterError, false)

This covers the full response side of the contract for the bare-agent path — the sibling DecoratorHandler test in the same file asserts only onResponseStart. Test-only change; no source touched.

Verified with the repo runner: borp -p "test/mock-*.js" → 339 pass / 0 fail; npm run lint → clean.

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 93.50%. Comparing base (17117f6) to head (c18375c).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #5763   +/-   ##
=======================================
  Coverage   93.50%   93.50%           
=======================================
  Files         110      110           
  Lines       39072    39072           
=======================================
+ Hits        36534    36535    +1     
+ Misses       2538     2537    -1     

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