As a Korifi app developer I want to see an error when I try to create a managed service instance of a disabled service plan

[georgethebeatle]

Dev Notes

• Rigth now in Korifi we do set service plan visibility on the service plan resource, but no controller observes it.
• We should error when a user tries to create an instance of a disabled service plan
• Existing instances in an errored state (as described above) should be able to recover once the plan is enabled.
• Ready instances should remain ready when their plan is disabled.
• All checks should happen in the controllers, so that kubectl users can have the experience as api users
• Think about whether is makes sense to spin off a separate story for org visibility or if we should deliver all three visibilities with one story
• What about space visibility?