PostgresJS error handling

We should wrap the postgres connection in an error handler to deal with any incomplete postgres setup issues which will inevitably arise. It should give helpful messages like:
If error connecting to database TBSP: first check if postgres is running (otherwise deal with that error), then ensure TBSP doesn't exist and tell user to `$ createdb TBSP` (or another name and supply `TBSP_DBNAME`)

Locate the Postgres connection setup and its existing error-handling path; the issue does not name a file or test. Review how connection failures and TBSP_DBNAME are currently handled, then define completion around helpful messages for a stopped Postgres service, a missing database, and the required createdb command.

Written by the indexing model from the issue text.