[Backport] Fix kitless multi-GPU tests and ROS link checks

[kellyguo11]

Description

Fixes two release CI failures without backporting #7405.

Kitless multi-GPU tests

Backports only the release-relevant multi-GPU test fix from #7540.

PR #7466 is present on release/3.0.0, so isaaclab.sh rejects a downloaded-Isaac-Sim link alongside the kitless image's active virtual environment. The test runner currently creates _isaac_sim -> /isaac-sim unconditionally because runtime mounts make /isaac-sim exist even in the kitless image.

This change creates the link only when /isaac-sim/python.sh exists. Kit-based test images retain their existing behavior, while the kitless multi-GPU smoke test resolves Python from VIRTUAL_ENV.

This intentionally excludes #7540's image-invariant/cache changes and all of #7405, which was not backported to the release branch.

Original PR: #7540

Documentation link check

The automatic backport's link check failed twice because www.ros.org and docs.ros.org return HTTP 403 to the GitHub runner. Both links remain valid. The link-check workflow already excludes known crawl blockers, so this adds a single ros.org exclusion covering both hosts without changing the documentation destinations or weakening checks for other domains.

Failed run: https://github.com/isaac-sim/IsaacLab/actions/runs/33828925399

Type of change

• Bug fix (non-breaking change which fixes an issue)

Release backport

Not applicable: this PR directly targets release/3.0.0.

Validation

• Added a regression test that failed against the unmodified release branch and passes with the multi-GPU fix.
• uv run --no-project --with pytest --with pyyaml python -m pytest docker/test/test_container_profiles.py -q - 14 passed.
• bash -n .github/actions/run-tests/run_tests.sh - passed.
• Parsed .github/workflows/check-links.yml with PyYAML and verified the exclusion matches both failing URLs.
• Applicable file-scoped pre-commit hooks - passed. The branch-wide changelog hook is not applicable to a release backport because it compares historical release differences against develop.
• The canonical uv run isaaclab -f command cannot resolve this branch's Linux/Windows-only lockfile on macOS; the equivalent file-scoped hooks were run directly.

Checklist

• I have read and understood the contribution guidelines.
• I have run the applicable pre-commit checks.
• Documentation destinations remain unchanged.
• My changes generate no new warnings.
• I have added a regression test for the multi-GPU behavior.
• No changelog fragment is required because no source package changed.
• The contributors already exist in CONTRIBUTORS.md.

[greptile-apps]

Greptile Summary

This backport prevents the multi-GPU test runner from treating the kitless image's mounted /isaac-sim directory as a downloaded Isaac Sim installation.

• Removes any existing _isaac_sim link and recreates it only when /isaac-sim/python.sh is executable.
• Adds a static regression test for the conditional-link requirement.

Confidence Score: 4/5

The PR appears safe to merge, with a non-blocking opportunity to make the new regression test verify shell behavior rather than source-line text.

The runtime change correctly distinguishes Kit-based and kitless layouts; the only accepted concern is that the added test can produce false confidence because it does not validate control flow.

Files Needing Attention: docker/test/test_container_profiles.py

Important Files Changed

Filename	Overview
.github/actions/run-tests/run_tests.sh	Correctly gates _isaac_sim creation on the presence of an executable Kit Python launcher, allowing kitless images to use VIRTUAL_ENV.
docker/test/test_container_profiles.py	Adds regression coverage, but its same-line substring assertion does not verify that the marker check controls symlink creation.

_{Reviews (1): Last reviewed commit: "Guard Isaac Sim link in kitless tests" | Re-trigger Greptile}

[greptile-apps]

Assertion does not verify guard

The assertion only checks that /isaac-sim/python.sh appears on the same source line as the symlink command, so an unconditional command with that path in a comment or unrelated expression still passes. This weakens the regression test because it does not verify that the executable check actually controls link creation.

[isaaclab-review-bot]

Isaac Lab Review Bot

Reviewed the CI backport’s conditional _isaac_sim link creation, ROS-domain link-check exclusion, and regression coverage. The changed paths preserve kit-based behavior while avoiding the kitless virtual-environment conflict; no actionable pre-merge defect is established.

• Design and architecture: The symlink guard remains localized to the container test runner’s existing setup point and distinguishes images by the executable Kit launcher. The source-inspection regression test is somewhat coupled to shell formatting and location, but this is a non-blocking maintainability tradeoff rather than a demonstrated defect.
• API: No public Python API, CLI argument, Compose contract, or environment contract changes. The tolerant link removal remains compatible with set -e, and subsequent isaaclab.sh -p calls retain their intended kit and kitless interpreter-resolution paths.
• Implementation: Checking for executable /isaac-sim/python.sh directly addresses the runtime-created directory ambiguity before creating _isaac_sim. The ros\.org exclusion covers both reported ROS hosts and follows the workflow’s existing substring-pattern style, with only the existing class of broad-match residual risk.

No blocking issues. No inline issue met the actionable-evidence threshold; the assessment above records the review feedback.

Automated review; human maintainers own approval decisions.

[kellyguo11]

run-ci