Log information about total # of reads attempted

The transaction level log tracing summary currently only shows the # of reads that returned a value. It would be nice to log the total number of reads the transaction made (even reads that found nothing).

Start by locating the transaction-level log tracing summary and trace where read attempts are counted versus reads that return a value. Update the summary to include total reads, including empty results, and verify the resulting log output with the relevant transaction tracing tests.

Written by the indexing model from the issue text.