[Documentation] Add pandas DataFrame usage example with SingleNodeExecutor.map (#968)

* Initial plan

* Add pandas DataFrame SingleNodeExecutor example to application docs

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* Move pandas DataFrame example from application.md to 1-single-node notebook

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* Add output and fix execution counts for pandas cell in 1-single-node notebook

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* fixes

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Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: jan-janssen <3854739+jan-janssen@users.noreply.github.com>
Co-authored-by: Jan Janssen <janssen@mpie.de>

Author: Copilot