fix(tests): prevent background uploads from racing VCR replay

[Abhijeet Prasad (AbhiPrasad)]

Unit tests could leave real background HTTP uploads running into later cassette-backed tests. In the failing Windows Python 3.14 job, test_span_filters_backend_parity escaped VCR replay and received a live API 401 while unrelated uploads were still running.

Make the memory logger fixture provide the same logger to worker threads, and use memory loggers in the span export and project-group tests that were starting real uploads. Tighten the asyncio.to_thread test to require both parent and worker spans; it fails before the fixture fix because only the parent is captured.

Validation:

• Full test_core session on macOS with Python 3.14.8 and --vcr-record=none: 1,090 passed, 106 skipped, 12 xfailed.
• Focused regression and affected tests: 11 passed.
• Diagnostic full-suite run confirmed only cassette-backed tests still use the HTTP background logger.
• Pre-commit checks passed. Windows validation remains for CI.

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-10-16T00:18:36.950008Z	eef4cbf	PR opened

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