Fieldservice Agreement Helpdesk Mgmt

This module connects Helpdesk tickets with Field Service orders and Agreements so that information is not re-entered by hand.

• On a Helpdesk ticket, the Agreement field now only offers agreements whose customer matches the ticket's customer, or whose service location matches the ticket's service location. This makes it harder to pick the wrong agreement.
• When a user creates a Field Service order from a ticket, the agreement and the service profile already selected on the ticket are copied onto the new order automatically. The user does not have to select them again on the order form.

The module extends the helpdesk.ticket model and adds a small view change on the standard Helpdesk ticket form. It does not add new menus or new screens of its own; the changes appear inside the existing Helpdesk ticket form and the Field Service order form that opens from the ticket. No new scheduled jobs, emails or automatic checks are added by this code.