test: cover OTel replay and user callback contexts

[zhongkechen]

Add Python handlers and SAM mappings for OTel cases 21–24: completed-step replay, active context in user functions and callbacks, and invocation retry status. Ordinary user spans inherit their active parent; handlers never attach replacement context or copy execution identity into probe spans.

Shared requirements: aws/aws-durable-execution-conformance-tests#131, pinned to 98b802cdb172614f98e217f7464784d47b9bb484 in the workflow and both test-ref defaults. This PR targets main and includes focused handler-context #756 and status-mapping #752. Merge those runtime prerequisites and the shared requirements first. Python #737 and its factory migration are excluded.

The handlers exercise public APIs across initial execution, wait/resume, failures, parallel/map branches, polling, callback submitters, retry helpers and virtual contexts. Tests verify canonical trace/parent IDs, exact probe counts, completed-body suppression and caller-context restoration. The shared coverage matrix documents initialization, policy, serialization and application-created thread boundaries that lack an active SDK-operation-span contract.

Validation:

• 65 conformance-package tests pass; wiring, focused types, formatting and bundles pass.
• 324 combined OTel tests pass against both the workspace core and the actual installed minimum core 2.0.0, with strict current-core assertions and explicit legacy behavior. Type checks cover 30 files. Direct scope cases cover same/unrelated/absent ambient parents, baggage, both samplers, success and failure.
• PR CI verifies core 2.0.0 is imported from site-packages and has no new optional handler hook, then runs the compatibility suite on Python 3.11–3.14. The package dependency floor remains unchanged.
• Real local exported traces pass seven of eight shared case/view checks. The remaining invocation-21 duplicate wait continuation also reproduces on unchanged main's local tester; its cloud case passes and assertions were not weakened.
• Normal PR CI runs all 24 cases in both views through ADOT/X-Ray and S3 against the exact SDK commit and pinned requirements. Current head dd69e05728c60647aae76202321f5d34b605c00e passes all applicable workflows and has no unresolved AI findings.

The failed-plus-uncovered conformance gate remains enabled. No IAM or workflow trust changes are included.

[github-actions]

Codex AI review

No actionable findings. Residual risk is limited to cloud-only conformance behavior, which was not executed during this read-only review.

Reviewed commit dd69e05728c60647aae76202321f5d34b605c00e. Workflow run