PPR - Streamline the addition of bulk assets to a registration

TODO - review scenario and provide full description

From client communication:
"And also other issue that I wanted to bring here is regarding assets addition when we ware performing the PPSA Registrations, BC online have option to add one asset at a time, and this is so tedious when we have to add 500 assets, can you please provide this feedback to the developer and see if they can add the option of adding 100 assets at one time. These types of services should be user friendly and help us not have the services which will give stress and waste unnecessary time."

No files, tests, or entry points are named. First clarify the registration workflow, the desired bulk-asset limit, validation and error handling, and whether the change spans the client and server; done means an agreed implementation scope and acceptance criteria for adding many assets at once.

Written by the indexing model from the issue text.