[Debug state] Add debug state for partition charts

[dej611]

Is your feature request related to a problem? Please describe.
Debug state is used to test chart components in Lens.

Describe the solution you'd like
Similar to XY chart debug serialized state, it would be useful to have a similar way to inspect a partition chart.

Describe alternatives you've considered

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

Kibana Cross Issues
Lens cross-referenced PR: elastic/kibana#86750

Checklist

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• this request is checked against already exist requests
• every related Kibana issue is listed under Kibana Cross Issues list

[dej611]

Just realized this is a duplicate of #917 . Sorry :)