Analyse shouldn't repartition to a single partition by default

analyse currently repartitions to a single partition, which will blow your computation up if you are running this on a query that isn't reducing very heavily, see

https://github.com/dask/dask/issues/11307

This shouldn't be the default behavior

cc @hendrikmakait

Start by tracing the analyse entry point and how it currently invokes repartition, then reproduce the failure mode described in the linked Dask issue with a query that does not reduce heavily. Done means analyse no longer repartitions to a single partition by default while preserving its intended analysis behavior.

Written by the indexing model from the issue text.