Replace semaphores in scoped services with a shared semaphore in a hosted service

[andchiind]

Describe the bug
Semaphores are being ignored since they are local to the current scoped service instance. Each time a different dependency injection is done, a new semaphore is created.

To Reproduce
Set the safezone status off and on several times while debugging. Updating the robot state is not truly being protected by a mutex.

Expected behavior
A semaphore should block any thread from accessing the protected code region. This can be done by storing them in hosted services which only have one instance at a time (as long as flotilla only uses one server at a time).

Screenshots

[andchiind]

A singleton might also work instead of a hosted service

[andchiind]

The only remaining problematic Semaphore is in RobotService.cs, but this will become redundant once #1279 is merged.

[andchiind]

It did not make it redundant, since the new update functionality does not work with currentArea in the Robot table

[oysand]

Consider removing the semaphore

[UsamaEquinorAFK]

Removes semaphores - #1323