test_runner: omit excluded coverage directories on the C++ side

[avivkeller]

By omitting the values we know will not be needed for test coverage from being serialized/deserialized, we can save time during coverage reporting.

We know that:

• node:* is not included in coverage
• /node_modules/ is not included coverage if coverageIncludeGlobs is not set

So, we omit on those cases.

[nodejs-github-bot]

Review requested:

• @nodejs/inspector
• @nodejs/test_runner

[avivkeller]

We don't have benchmarks for this yet, but a local fixture took 0.93s (after) vs 1.16s (before). Not sure if the speedup is worth the "hackiness" of JSON manipulations in this PR.

(I'll fix the errors after a round of feedback)

[codecov]

Codecov Report

❌ Patch coverage is 70.99237% with 38 lines in your changes missing coverage. Please review.
✅ Project coverage is 90.12%. Comparing base (45d6d31) to head (db1d6bf).
⚠️ Report is 4 commits behind head on main.

Files with missing lines	Patch %	Lines
src/inspector_profiler.cc	74.38%	13 Missing and 18 partials ⚠️
lib/internal/test_runner/coverage.js	30.00%	7 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #65371      +/-   ##
==========================================
- Coverage   90.13%   90.12%   -0.01%     
==========================================
  Files         752      752              
  Lines      251872   251981     +109     
  Branches    47359    47388      +29     
==========================================
+ Hits       227033   227108      +75     
- Misses      16167    16187      +20     
- Partials     8672     8686      +14     

Files with missing lines	Coverage Δ
src/inspector_profiler.h	85.71% <ø> (ø)
lib/internal/test_runner/coverage.js	59.22% <30.00%> (-0.35%)	⬇️
src/inspector_profiler.cc	82.29% <74.38%> (+0.34%)	⬆️

... and 27 files with indirect coverage changes

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