fix: Prevent ST from holding onto Event refs in memory when aborted

[cwli24]

Releases the Event entries the agent hold onto in Trace after it has aborted. This addresses a known case of memory leak caused by continuing to add those references to a Set that is never cleared.

Overview

Related Issue(s)

https://new-relic.atlassian.net/browse/NR-420780

Testing

Jest added

[github-actions]

Supportability Metric Usage Changes:

No matching changes found

Supportability Metrics .md File Changes:

supportability_metrics.md was changed? false

New supportability metrics require changes to supportability_metrics.md, as well as a new PR to Angler. Please ensure an Angler PR is created and linked to this PR.

[github-actions]

Asset Size Report

Merging this pull request will result in the following asset size changes:

Agent	Asset	Previous Size	New Size	Diff
lite	loader	24.97 kB / 9.47 kB (gzip)	24.97 kB / 9.47 kB (gzip)	0% / 0% (gzip)
lite	async-chunk	52.6 kB / 17.45 kB (gzip)	52.6 kB / 17.45 kB (gzip)	0% / 0% (gzip)
pro	loader	52.91 kB / 18.61 kB (gzip)	52.91 kB / 18.61 kB (gzip)	0% / -0.02% (gzip)
pro	async-chunk	91.84 kB / 28.46 kB (gzip)	92 kB / 28.53 kB (gzip)	0.18% / 0.21% (gzip)
spa	loader	61.66 kB / 21.31 kB (gzip)	61.66 kB / 21.31 kB (gzip)	0% / 0% (gzip)
spa	async-chunk	116.46 kB / 35.44 kB (gzip)	116.63 kB / 35.49 kB (gzip)	0.14% / 0.16% (gzip)

[github-actions]

Last ran on June 06, 2025 17:38:12 CDT
Checking merge of (d0f0730) into main (66f5eb8)

[codecov]

Codecov Report

Attention: Patch coverage is 59.25926% with 11 lines in your changes missing coverage. Please review.

Project coverage is 87.61%. Comparing base (66f5eb8) to head (d0f0730).
Report is 3 commits behind head on main.

Files with missing lines	Patch %	Lines
.../features/session_trace/aggregate/trace/storage.js	57.69%	7 Missing and 4 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1491      +/-   ##
==========================================
- Coverage   87.70%   87.61%   -0.10%     
==========================================
  Files         197      197              
  Lines        7746     7761      +15     
  Branches     1554     1563       +9     
==========================================
+ Hits         6794     6800       +6     
- Misses        820      826       +6     
- Partials      132      135       +3     

Flag	Coverage Δ
unit-tests	78.71% <59.25%> (-0.02%)	⬇️

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[ellisong]

LGTM