chore: improve process hang visibility

[tinker-michaelj]

Description:

• Closes Gain visibility into why subprocess ProcessHandle.destroy() is flaky #16478
• If a SubProcessNode fails to stop, uses jcmd to dump its threads to the output/test-clients.log error redirect file.

[codacy-production]

Coverage summary from Codacy

See diff coverage on Codacy

Coverage variation	Diff coverage
✅ +0.00% (target: -1.00%)	✅ ∅

Coverage variation details

	Coverable lines	Covered lines	Coverage
Common ancestor commit (539105d)	96496	62809	65.09%
Head commit (e20fc12)	96496 (+0)	62809 (+0)	65.09% (+0.00%)

Coverage variation is the difference between the coverage for the head and common ancestor commits of the pull request branch: <coverage of head commit> - <coverage of common ancestor commit>

Diff coverage details

	Coverable lines	Covered lines	Diff coverage
Pull request (#16485)	0	0	∅ (not applicable)

Diff coverage is the percentage of lines that are covered by tests out of the coverable lines that the pull request added or modified: <covered lines added or modified>/<coverable lines added or modified> * 100%

See your quality gate settings    Change summary preferences

_{Codacy stopped sending the deprecated coverage status on June 5th, 2024. Learn more}

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 63.35%. Comparing base (539105d) to head (e20fc12).
Report is 2 commits behind head on develop.

Additional details and impacted files

@@            Coverage Diff             @@
##             develop   #16485   +/-   ##
==========================================
  Coverage      63.35%   63.35%           
- Complexity     20099    20100    +1     
==========================================
  Files           2527     2527           
  Lines          93677    93677           
  Branches        9804     9804           
==========================================
  Hits           59349    59349           
  Misses         30730    30730           
  Partials        3598     3598