Reconsider how Staff Persons are filtered for use in the various forms

[marshalc]

Whilst looking to clean up Issue #180, it has become apparent that a number of these duplications are due to being contacts for P & T forms in different roles. When you select Theatre Contact or Transplant Co-Ordinators, these try to filter existing Staff Persons based on their Jobs - the logic being that these people crop up in these roles more than once, so limiting the list of all the contacts to them should make it easier to find them.

However, this has the drawback of meaning that existing records where they have another job are excluded from the listing, and thus a new record is created. This isn't the expected behaviour, and with the unique constraints added by #180 to reduce the other duplications, this needs a reworked solution.

[marshalc]

However, until the work on removing Worksheet from Samples is completed, P and T forms won't load in the development system, so we can't address this in practice.

[marshalc]

• Staff is a new app, so there is a modal process for creating users
• All staff are now available in the selection listing, so duplication should be reduced by improved visibility
• Staff are added to their relevant groups on save of P & T forms for Perf Tech and Theatre Contacts

Considering this task resolved already