We recently changed the intentions form to take a full model of a dc rather than just the string identifier (so {Name: 'dc', Primary: true} vs just 'dc' in order to know whether the DC is the primary or not.
Unfortunately, we only did this on the global intentions page not the per service intentions page. This makes it impossible to save an intention from the per service intention page (whilst you can still save intentions from the global intention page as normal).
The fix here pretty much copy/pastes the approach taken in the global intention edit template over to the per service intention edit template.
Tests have been added for creation in the per service intention section, which again are pretty much just copied from the global one, unfortunately this didn't exist previously which would have helped prevent this.
