Assign case to a different client

Rationale
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If a Case is opened and assigned to the wrong contact (client), user needs a way to reassign it.

Implementation
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Add action link to case selector (dashboard, find case and case tab): "Assign to Another Client". This link wil

Implementation
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1. Add "Assign to Another Client" link to Case Summary fieldset on Manage Case screen (contact/view/case).

2. Clicking link shows autocomplete contact search field + 'Assign' button.

3. Assign processing does the following:

• Prompt for confirmation: 'Are you sure you want to reassign this case and all related activities and relationships to $selectedContactName?'

• Make a complete copy of the currently viewed case (includes linked case_activities)

• When copying case activities, if an activity target_contact_id = dupe contact id, then the copy should set target_contact_id = newly assigned contact id. This 'fixes' the case 'client' for these activities to point to the right contact id.

• Case roles (relationships linked to this case via relationship.case_id) need to have both the case_id and the contact_id_a values updated (contact_id_a becomes the contact_id of the newly assigned contact who is now 'the client').

• Auto-add an activity on the new case (activity type = "Reassigned Case") with subject "Case 1234 reassigned from contact id 516 to contact id 923. New Case ID is 3211."

• Mark the original case, and related case activities as deleted (is_deleted = 1).