tools: add lint rule for aborted AbortController

[trivikr]

This adds an ESLint rule to prefer AbortSignal.abort() when a test creates an
AbortController, immediately aborts it, and only uses the resulting
controller.signal.

The rule is intentionally conservative and only fixes the simple already-aborted
signal pattern from #63489.

---

The rule uses ESLint scope analysis rather than text matching. After finding a
candidate declaration, it gets the declared variable with
sourceCode.scopeManager.getDeclaredVariables() and checks all references to
that variable.

It only reports when the variable has exactly two non-declaration references:

1. the immediate controller.abort() call
2. one controller.signal read

If the controller is logged, passed somewhere else, aborted later, read more than
once, or otherwise referenced, the rule does not report or autofix it.

---

Assisted-by: openai:gpt-5.5

[nodejs-github-bot]

Review requested:

• @nodejs/quic

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.31%. Comparing base (4639dcb) to head (a506493).
⚠️ Report is 7 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #63541      +/-   ##
==========================================
+ Coverage   90.29%   90.31%   +0.02%     
==========================================
  Files         730      730              
  Lines      234695   234695              
  Branches    43956    43955       -1     
==========================================
+ Hits       211927   211974      +47     
+ Misses      14494    14436      -58     
- Partials     8274     8285      +11     

see 48 files with indirect coverage changes

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[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/73798/