Gracefully handle multiple people using `plandev`

[DominicOram]

If I am remotely debugging BlueAPI using plandev and another person tries to do the same it not only fails to connect on their side but also brings my connection down too. It's understandable that there is a limitation on only one person being able to use plandev at the same time but we should look into making potential clashes as graceful as possible.

Acceptance Criteria

• There is some amount of investigation on what options we have in this case
• If we can make things cleaner easily we do