Fix cmake version for uv build from source packages on aarch64

[peterd-NV]

Description

Fixes uv run --extra mimic failing during dependency resolution on Linux aarch64 systems using CMake 4.

This is a follow-up to #6717 that added CMAKE_POLICY_VERSION_MINIMUM=3.5 handling around ARM dependency builds performed by the Isaac Lab installer.

This PR extends the same compatibility policy to uv's package-specific build environment.

Fixes # (issue)

Fixes failing build for Isaac Lab Mimic when running uv.

Type of change

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

Checklist

• I have read and understood the contribution guidelines
• I have run the pre-commit checks with ./isaaclab.sh --format
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• I have added a changelog fragment under source/<pkg>/changelog.d/ for every touched package (do not edit CHANGELOG.rst or bump extension.toml — CI handles that)
• I have added my name to the CONTRIBUTORS.md or my name already exists there

[greptile-apps]

Greptile Summary

This PR configures uv to pass CMake’s compatibility-policy floor specifically when building the source-only egl-probe dependency, allowing Mimic dependency resolution on CMake 4 hosts.

• Adds the package-specific uv build variable for egl-probe.
• Adds a regression assertion for the root pyproject configuration.
• Documents the CMake 4 compatibility fix in the Isaac Lab changelog.

Confidence Score: 5/5

The PR appears safe to merge, with no concrete regressions or blocking failures identified.

The build variable is scoped to the exact source-only dependency that requires CMake compatibility handling, and its reachable Linux build paths do not reveal a conflicting platform contract.

Important Files Changed

Filename	Overview
pyproject.toml	Adds a narrowly scoped uv build variable matching the resolved source-only egl-probe package.
source/isaaclab/test/cli/test_uv_run_pyproject.py	Verifies that the root uv configuration retains the required package-specific CMake policy variable.
source/isaaclab/changelog.d/uv-egl-probe-cmake4.rst	Records the corrected uv run --extra mimic behavior on CMake 4.

_{Reviews (1): Last reviewed commit: "fix cmake version for uv build from sour..." | Re-trigger Greptile}

[isaaclab-review-bot]

Isaac Lab Review Bot

Adds a package-scoped uv build variable for egl-probe, setting CMAKE_POLICY_VERSION_MINIMUM=3.5 to support CMake 4 when resolving the mimic extra. The change includes a focused configuration test and changelog fragment.

• Design and architecture: The compatibility override is scoped to the egl-probe build rather than applied globally, preserving unrelated package builds and existing uv resolution, index, and dependency override behavior.
• API: No public Python APIs, CLI arguments, extras, or dependency defaults are changed. The additive [tool.uv] configuration affects only the build environment for the normalized egl-probe package name.
• Implementation: The TOML entry is placed correctly in the existing [tool.uv] table, and the regression test verifies the exact package-specific variable mapping. The test validates repository configuration rather than executing an actual CMake 4 source build, leaving that end-to-end path dependent on CI or platform validation.

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.