Restrict team members from marking themselves as unavailable on dialer

Currently, agents/team members have the ability to manually change their status to “Unavailable” from the JustCall dialer. This gives them control to go offline at any time, which leads to inconsistent call coverage and disrupts the overall workflow.

The user requests a feature where only admins or supervisors can control the availability status of agents. Agents should not be able to manually mark themselves as unavailable.

Expected Behavior: Availability/unavailability should be managed centrally (by admins or working hours), ensuring consistent workforce availability - Roles and permissions should have this control so that admin can change the behaviour as per need.