update references to 26.08.1

[jperez999]

Description

Completed the PR #2574-equivalent release update for 26.08.1.

• Updated active release references to 26.08.1; Helm Chart.yaml and service.image.tag use the prior format: 26.8.1.
• Renamed the managed Helm example to managed-helm-nrl-26.08.1.yaml.
• Retained the single 26.05 reference only as the intentional historical link to the prior release notes.
• Validation passed: 88 targeted tests, Helm lint, Ruff, whitespace check, and all pre-commit hooks.

Checklist

• I am familiar with the Contributing Guidelines.
• New or existing tests cover these changes.
• The documentation is up to date with these changes.

[copy-pr-bot]

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[greptile-apps]

Greptile Summary

This follow-up corrects release-branch references while retaining the 26.8.1 artifact and publication version.

• Checks out documentation from the 26.08 release branch.
• Derives the 26.08 source branch when releasing patch version 26.08.1.
• Updates Helm, service, documentation, examples, and tests to the new release version.

Confidence Score: 5/5

The PR appears safe to merge.

No blocking failure remains; the previously invalid documentation release ref now resolves to the 26.08 release branch.

Important Files Changed

Filename	Overview
.github/workflows/nrl-docs-nvidia-publish.yml	Correctly separates the 26.08 content branch from the 26.8.1 published documentation version.
.github/workflows/perform-release.yml	Adds patch-version parsing so 26.08.1 releases build from the corresponding 26.08 branch.
README.md	Corrects the supported-release link to point to the 26.08 branch.
nemo_retriever/helm/Chart.yaml	Updates Helm release metadata to the chart’s 26.8.1 version format.
nemo_retriever/helm/values.yaml	Updates the default service image tag to 26.8.1.

_{Reviews (2): Last reviewed commit: "fix versioning formatting" | Re-trigger Greptile}

[kheiss-uwzoo]

lgtm

[kheiss-uwzoo]

per Sohail's observation 26.08.1 or 26.8.1?

[kheiss-uwzoo]

26.08.1