[Docs Overhaul] --extra usage explained, and fixes to commands

[StafaH]

Description

Adds a section for explain --extra usage for uv run, and links it to the install and preset.

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

The PR clarifies how to select optional dependencies with uv run, centralizes the available extras and compatibility guidance, and associates physics and visualization choices with their required extras.

• Replaces combined OV backend examples with focused OV PhysX commands.
• Adds a reusable optional-extras reference section and links to it from the installation and quickstart pages.
• Expands quickstart tables with required-extra information.

Confidence Score: 5/5

The documentation-only PR appears safe to merge with no actionable defects identified.

The changed commands, extra names, compatibility guidance, and Sphinx references align with the checked project configuration and documentation structure.

Important Files Changed

Filename	Overview
docs/source/setup/installation/index.rst	Updates OV PhysX examples and adds a referenced catalog of optional extras and incompatible backend combinations.
docs/source/setup/quickstart.rst	Aligns the quickstart command with the OV PhysX-only extra and documents required extras for physics and visualization selectors.

_{Reviews (1): Last reviewed commit: "Add more detail to install docs for -ext..." | Re-trigger Greptile}

[isaaclab-review-bot]

Isaac Lab Review Bot

The documentation usefully centralizes uv run --extra guidance and links the quickstart to a shared extras reference, but two inconsistencies need correction: rl-games is presented as an installable package extra despite the page stating it is not included in wheel extras, and the expanded backend table leaves several rows without the required third cell.

• Design and architecture: Centralizing optional-extra documentation under the new installation-optional-extras target is a sound way to avoid duplicated guidance, and the new cross-references use that structure consistently. The shared section must clearly distinguish source-project extras from published wheel extras.
• API: The documented placement of uv run --extra, supported selector forms, and alignment of --extra ovphysx with physics=ovphysx are consistent. However, listing rl-games alongside extras installed through uv pip install "isaaclab[<extra>]" or uv add contradicts the existing statement that rl_games is not included in wheel extras and requires separate installation.
• Implementation: The visualizer table was fully converted to three columns, but the backend table adds a Required extra column without adding a third cell to the Isaac Sim PhysX and renderer rows. The list-table therefore has inconsistent row widths and must be completed so docutils can render it.

Minor fixes needed. Posted 2 actionable findings inline.

Automated review; human maintainers own approval decisions.

[isaaclab-review-bot]

🟡 Warning · Implementation — rl-games listed as unavailable wheel extra

This section tells users to install extras via uv pip install "isaaclab[<extra>]" / uv add, yet the same page states a few lines below that "The rl_games package is not included in wheel extras; install it separately when required". Listing rl-games here sends readers to an install command that will not provide the framework. Remove it, or explicitly separate source-project uv run extras from published wheel extras.