Proposal: update Find Encounters Query

Use-case: Helse Vest need some sort of query to get hold of a list of patients 'currently sitting in the waiting room of a department' (waiting for any type of encounter).

Proposal: document the fact that an encounter may become 'active' by the mere fact that a patient has arrived and is in the waiting room. The Encounter (in EVN mood) has started. The encounter.effectiveTime interval hasn't started yet; the encounter.administrativeTime interval has however started (or hasn't it?)

The current Encounter Query doesn't fulfill the Helse Vest use-case:

• The current query contains a mandatory Patient.id (the use case calls for an optional Patient.id parameter)
• Rename the QueryByParemeterPayload class back to QueryByParameter. The same name is used in all queries - and yet this query used a differenmt clone name. I know of no reason why the name should be different...
• Response model should include the ID of the Appointment Encounter