Global read-only and read-only workflows

[MariusVuscanNx]

Implemented two levels of read-only:

• Global read-only that can be set at the engine level by

  .UseWorkflowsApi(api =>
  {
        api.UseReadOnlyMode();
  })
  

  If enabled, publish, unpublish, delete, create, update references, bulk actions (except export), import, import files are not allowed
• Adjusted the existing read-only workflows functionality If attribute enabled, then publish, retract, delete, import and update references are not allowed.

For both levels, links were exposed to be handled in the designer by leveraging the HATEOAS method.