Use ResultClass::HashRefInflator instead of building array with iteration

**NB** This is an incomplete solution as it does not include retrieval of the topics yet.

This retrieves a projection of the required columns into the instant answer list array.

On my test environment, run time for this query goes from ~700ms to ~70ms.
@jbarrett Feel free to remove perl_module and attribution, we don't need those in the index :)