[TASK-API:] Implement `api/dcim/devices` endpoints

[ByteOtter]

You would like to suggest a new feature?

To manage individual devices we need to implement GET, POST, PUT, PATCH and DELETE methods for this endpoint.

Checklist:

• [x] #42
• [x] #43
• [x] #45
• [x] #44
• [x] #46

[ByteOtter]

Will be taken care of by Thanix.