[zhongkechen]

Add OpenTelemetry conformance coverage for replay and callback delivery through the public SDK APIs.

Coverage

• Case 21: completed steps reuse saved results during replay.
• Cases 22–23: user-function and callback code retain the expected tracing context.
• Case 24: invocation retry status is represented correctly.
• Case 25: caught callback failures without error details retain the expected result, status and replay behavior.
• Case 26: an externally completed callback reaches the exporter before the observed step runs. Its raw terminal export count remains one across both later replay barriers and final completion. Parent/trace identity and span timestamps are checked separately.

The change includes handlers, SAM/Makefile mappings, local integration tests, documentation and immutable workflow/catalog pins. Handlers use the Core 3 / OTel 2 factory API.

Stack

main → #758 → #795 → #796

#758 provides the Core/OTel runtime fixes. #795 aligns the local testing service's replay visibility and update acknowledgment with the service. This PR adds the conformance coverage that depends on those layers.

Validation

All 112 local conformance-package/workflow checks pass, along with package lint, formatting and commit-message checks. Unit observers accept repeated natural End observations and verify detached error copies; exported-span and error-payload assertions remain strict. Conformance handlers and requirements are unchanged by those observer adjustments. Delaying the case-26 callback's first rendering until invocation 3 or 4 is rejected by the live exporter assertion; recorded timestamps alone no longer let those regressions pass.

Shared conformance #131, including the strengthened chained-invoke parent/ancestry qualification, remains a merge prerequisite. Local results do not replace that qualification.

[github-actions]

Codex AI review

No actionable findings. The prior callback export-phase gap is addressed. Review was static: tests were not run, and external workflow/catalog compatibility was not verified.

Reviewed commit 14e6d62d0135dcbfbad354c6781d0ad17fa14d45. Workflow run