[Research] store extension specific visualizations in system index or create new index

[kavilla]

System index for OpenSearch Dashboards is .kibana. Do we want the ability to store in that index or should we just create an index per an extension and store/clean up within that index?

[kavilla]

This impacts "security" should we do document based security vs index security.

[saratvemulapalli]

There are pro's and con's for each approach. I believe having one index for each extension is overkill to operationally maintain them.
Whats the data we'd like to store in this index? I would love to see an example.