This main feature of this pr is adding the possibility to login with multiple employees on the list view and kanban view of workorders.

There is now a button in the header that will allow to log in as an employee in the list view.
The flow is the following :
- The employee logs in
- He becomes the "admin" of the session and his name appears next to the log out button.
- If another employee logs in, he will become admin and the first one will no longer be visible in the header.
- The employee will start timesheeting on the workorder if he press the start button. Notice that the employees working on the workorder will appear in the last column of every work_order record.
- If this second employee logs out, the first one will not become admin automatically. He will first need to click on his name/avatar in the popup and will be asked his pin code (if needed) to log in again.

There is also a way to assign employees to a workorder.
A filter will help retreive the workorder on wich the admin of the session has been assigned.
In addition, a new button in the header allows to mark as done multiple workorders at once.

The timer component has been updated to avoid wrong values if the computer goes to sleep mode.

The wizard of the workorders allowing to see the time traking has also be modified (switching tabs) and automated (changing duration will update end date e.g.)

From a more technical point of vue, the employees and admin will be saved in the session.
The employees working on a workorder will be saved on the record.

Task : 3063632

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