Previous we were re-processing all ledgers for every position msg
received from the API, per client.. Instead do that once in a first pass
and drop all key-miss lookups for `bs_mktid`s; it should never happen.
Better typing for in-routine vars, convert pos msg/objects to `dict`
prior to logging so it's sane to read on console. Skip processing
specifically option contracts for now.
c3686185c1