`clear-all.sh` doc

**Describe the feature you'd like**

Add some usage instruction and limitations on `clear-all.sh` in docs

**Additional context**

Add any other context or screenshots about the feature request here.

Find the clear-all.sh script in the repository, likely in a scripts or tools directory. Review its current content and usage in the project. Look for existing documentation files, such as README.md or docs/, to see where to add instructions and limitations. Ensure the documentation explains what the script does, how to run it, and any important caveats.

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