ci: enforce standard hosted runners

[GraciousGazelles]

Summary

• tighten the workflow runner policy to reject Ubuntu slim and Ubuntu ARM labels
• move existing Linux ARM and slim runner entries onto standard Ubuntu hosted labels
• keep the runner-policy regression coverage aligned with the stricter baseline

Validation

• git diff --cached --check

[github-code-quality]

Code Coverage Overview

Languages: TypeScript, Python

TypeScript / code-coverage/typescript-sdk

The overall coverage remains at 48%, unchanged from the main branch.

Python / code-coverage/python-tools

The overall coverage in the w7091-runner-policy-... branch remains at 64%, unchanged from the main branch.

Show a code coverage summary of the most impacted files.

File	main b598d2f	w7091-runner-policy-... 33dd7b5	+/-
.github/scripts..._ci_planners.py	100%	100%	0%
.github/scripts...kflow_policy.py	85%	86%	+1%

Python / code-coverage/python-sdk

The overall coverage remains at 82%, unchanged from the main branch.

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_{Updated June 30, 2026 22:21 UTC
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[gemini-code-assist]

Code Review

This pull request updates the workflow policy script to disallow non-standard public runner labels, specifically removing support for 'slim' and '-arm' variants of Ubuntu and Windows runners. It also updates the test suite to reflect these changes, including adding a new test to verify that these non-standard labels are rejected. There are no review comments, so I have no feedback to provide.

Important

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[GraciousGazelles]

Closing this PR: the runner labels it changed are standard GitHub-hosted runner labels for public repositories, so this change is not needed for the current runner policy boundary.