Allow entities to be deleted/cleared locally

[seadowg]

~~Blocked by #6011~~

Entities that are created/locally should be deletable like other data in the app. Users should not be able to delete an instance that has created/updated an entity (to prevent data inconsistencies with the server), but should be able to clear all saved forms/entities out at once from settings.

Acceptance

• [ ] Given I've created an entity locally When I reset "Saved forms and entities" (in "Project management" settings) Then the entity no longer appears in follow up forms And the entity does not appear in "View local entities"

• [ ] Given I've created an entity locally When I navigate to "Delete saved form" Then the instance that created the entity does not appear in the list

• [ ] Given I've created an entity locally And submitted the form that created it And it has been approved And the entity list has been updated When I delete the instance that created it via "Delete saved forms" Then the entity still appears in follow up forms

• [ ] Given I've updated an entity locally And a previous version of the entity was in an entity list When I reset "Saved forms and entities" (in "Project management" settings) Then the previous version is shown in follow up forms And the previous version appears in "View local entities"

• [ ] Given I've updated an entity locally When I navigate to "Delete saved form" Then the instance that updated the entity does not appear in the list

Questions

1. Where/how should we store entities? This feels like the right place to make that decision.