This ticket is a downstream follow-up to SERVER-31782, which adds support for the allowPartialResults option on aggregation commands.

As part of that work, allowPartialResults also needs to be added to the aggregation $queryStats key so that query stats can distinguish between requests where the option is omitted, explicitly true, and explicitly false. This changes the shape of $queryStats output for aggregation queries and may affect downstream consumers that read or process query stats data.

Tipp: This ticket did something simular so it might be worth looking at: DPIPE-9717