Improve data integrity for dex data

[cronokirby]

There are several issues in the vein of penumbra-zone/web#2158 relating to the data on the explore page being incorrect. We should take a second look at the table calculations in pindexer, and try and squash these issues.

In particular, we want to make sure that the aggregate summary reflects the summary for each pair, and that we handle the fact that we ultimately want metrics that capture both side of a pair in pindexer, rather than doing this calculation on the web side of things.