I ended up with minutes-long open transactions in the database in prod
which was causing outtages. This is because I thought transactions were
basically free, which is a terrible thing to think. Instead we'll just
open them when we need them.
This is a huge change. I was getting really sick of the split between
nuisance/water tables when more than half of the data they store is
common. I finally bit off the big work of switching it all.
This creates a single unified table, publicreport.report and copies the
existing report data into it. It also ports existing data from the
original tables into the new table.
Along with all of this I also overhauled the system for handling
asynchronous work to use a LISTEN/NOTIFY connection from the database
and a single cache table to avoid ever losing work.
This refactor was born out of the inter-dependency cycles developing
between the "background" module and just about every other module which
was caused by the background module becoming a dependency of every
module that needed to background work and the fact that the background
module was also supposedly responsible for the logic for processing
those tasks.
Instead the "background" module is now very, very shallow and relies
entirely on the Postgres NOTIFY logic for triggering jobs. There's a new
table, `job` which holds just a type and single row ID.
All told, this means that jobs can be added to the queue as part of the
API-level or platform-level transaction, ensuring atomicity, and
processing coordination is handled by the platform module, which can
depend on anything.
