fix(otel): remove OpenTelemetry upper bounds

[zhongkechen]

Summary

• remove the temporary OpenTelemetry <=1.42.1 upper bounds from package dependencies
• remove the same cap from Hatch test and type-check environments
• update the OTel package requirements documentation

Why

The cap was added to remain compatible with the ADOT Lambda layer. Upstream fixed the incompatibility in AWS OTel Python instrumentation v0.19.0, so retaining the restriction would unnecessarily prevent consumers and development environments from resolving newer OpenTelemetry releases.

Impact

Consumers can use OpenTelemetry versions newer than 1.42.1 while the existing minimum API and SDK version remains 1.20.0.

Validation

• hatch run dev-otel:test (105 passed)

[github-actions]

Claude AI review

No actionable findings.

This PR removes the temporary opentelemetry-* <=1.42.1 upper bounds from the otel package dependencies (packages/aws-durable-execution-sdk-python-otel/pyproject.toml), the root Hatch test/type-check/PyPI-otel environments (pyproject.toml), and the OTel package README (packages/aws-durable-execution-sdk-python-otel/README.md). The change is purely a dependency-metadata / documentation change with no runtime code touched.

I verified:

• All OTel <=1.42.1 occurrences in the repo are removed; no stray caps remain in pyproject.toml files, CI workflows, or requirements/lock files. (The remaining 1.42.1 matches are boto3>=1.42.1, which is unrelated.)
• The retained >=1.20.0 minimums are unchanged and consistent between the package metadata and README, matching the PR description.
• The opentelemetry-exporter-otlp entry now carries no version constraint (was cap-only), which is intentional and consistent with the README.

Residual test risk: this only affects dependency resolution, not the pinned versions actually exercised. CI installs continue to resolve whatever the resolver picks, so newer OpenTelemetry releases (>1.42.1) are not directly pinned/tested by this change — a future breaking OTel release could surface only at consumer install/runtime rather than in this repo's test matrix. That is an accepted trade-off of removing the cap and not a defect in the diff.

Reviewed commit 7afbec8d556c8b68c0d14b82d557c2a6e6661b9c. Workflow run

[github-actions]

Codex AI review

No actionable findings. Residual risk is limited to compatibility with future, not-yet-tested OpenTelemetry releases admitted by the widened constraints. Tests were not run per review constraints.

Reviewed commit 7afbec8d556c8b68c0d14b82d557c2a6e6661b9c. Workflow run