[NEOS-576] Expose ability to fine tune batch size for sql insert

[nickzelei]

This is variable based on network latency and other pressures.

We should work towards exposing this for the select too, but starting with the output is a good first step.

It would also be good to allow fine tuning of connection limits as well as max in flight.

Benthos has a list of settings it supports on their sql_raw docs page.

_{From SyncLinear.com | NEOS-576}