Core: reduce allocations in metrics.getMetrics

[patmmccann]

Motivation

• getMetrics() allocated a new object for each visited node during depth-first traversal which increased GC pressure on hot paths that repeatedly call metrics aggregation.

Description

• Replace the per-node Object.assign({}, ...) allocations with a single mutable accumulator object and guarded writes via hasOwnProperty so nearest metrics keep precedence and includeGroups behavior is preserved.
• Change made in src/utils/perfMetrics.ts (metrics aggregation path only).

Testing

• Ran npx eslint --cache --cache-strategy content src/utils/perfMetrics.ts test/spec/unit/utils/perfMetrics_spec.js and it passed.
• Ran npx gulp test --nolint --file test/spec/unit/utils/perfMetrics_spec.js and the spec suite passed (49 tests completed).

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Codex Task

[coveralls]

Coverage Report for CI Build 24765613806

Coverage increased (+0.001%) to 96.39%

Details

• Coverage increased (+0.001%) from the base build.
• Patch coverage: 7 of 7 lines across 1 file are fully covered (100%).
• No coverage regressions found.

Uncovered Changes

No uncovered changes found.

Coverage Regressions

No coverage regressions found.

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Coverage Stats

Relevant Lines:	229272
Covered Lines:	220996
Line Coverage:	96.39%
Relevant Branches:	53201
Covered Branches:	43252
Branch Coverage:	81.3%
Branches in Coverage %:	No
Coverage Strength:	72.75 hits per line

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💛 - Coveralls