This returns an error for trying to update or insert into invalid columns, without hitting the database. This change also switches from `json_populate_recordset` for these operations `json_to_recordset` which should make no functional difference except allowing future flexibility.
This required untangling logic from App.hs.
Building/rejecting a plan no longer consumes a pool connection.
* Added io test for failed resource embedding not consuming connection
* optionalrollback to Query.hs and Response.hs
* delete Middleware module
* remove plan logic from App.hs
* remove RequestContext
* remove pkCols logic from App.hs
* remove proc logic from App.hs
* remove config logic from handleRequest
