* Sync canonical Python 3.15 test maintenance
Apply update_lib cleanup and accounting, warning, and documentation updates while preserving stack-safety, Cargo path, and missing-native adaptations. Remove only unused helper and import remnants; do not add new tests or runtime claims.
Assisted-by: OpenAI Codex: model version unavailable
* Sync canonical SystemTap companion fixtures
Copy the existing expected trace and GC probe template through update_lib to match the already canonical consumer and Python input. Preserve the tracing capability gate; validate source consistency without invoking tracing tools or claiming provider support.
Assisted-by: OpenAI Codex: model version unavailable
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Co-authored-by: Codex <codex@openai.com>