Is your feature request related to a problem or challenge?

I would like to propose DataFusion add the Postgres percentile_cont aggregation function. This would be the exact counterpart to the existing approx_percentile_cont.

Describe the solution you'd like

It looks like it would be relatively straightforward to generalize the existing median implementation into percentile_cont.

Describe alternatives you've considered

No response

Additional context

I may work on this soon unless there are objections.