This PR adds a usage of the new ActionScope primitive for the wallet's use cases. The idea is primarily to give a place for every transaction method to put their transactions and look at the transactions that have already been generated. It hooks into .add_pending_transactions which is the primary endpoint for adding transaction state changes to the database. This function was tweaked (hiding whitespace will help in review) to work better with the paradigm. It should probably be multiple functions and the only endpoint should be the action scope, but that feels out of scope for this change.