LineKeyType
* `PRIMARY_LINE` - PRIMARY_LINE is the user's primary extension. This is the default assignment for Line Key Index 1 and cannot be modified. * `SHARED_LINE` - Shows the appearance of other users on the owner's phone. * `MONITOR` - Enables User and Call Park monitoring. * `CALL_PARK_EXTENSION` - Enables the configure layout feature in Control Hub to set call park extension implicitly. * `SPEED_DIAL` - Allows users to reach a telephone number, extension or a SIP URI. * `OPEN` - An open key will automatically take the configuration of a monitor button starting with the first open key. These buttons are also usable by the user to configure speed dial numbers on these keys. * `CLOSED` - Button not usable but reserved for future features. * `MODE_MANAGEMENT` - Allows users to manage call forwarding for features via schedule-based routing.