Add a simulated camera which changes based on positioners

Description

Adds a StageCameraProxy proxy device which makes a SimCamera return an ROI of an image based on the positions of samx and samy

Related Issues

Closes bec#394 (closed)

Screenshots / GIFs (if applicable)

Test example

Add the config:

oav:
  readoutPriority: async
  deviceClass: ophyd_devices.SimCamera
  deviceConfig:
    device_access: true
  deviceTags:
    - detector
  enabled: true
  readOnly: false
  softwareTrigger: true

camera_stages_proxy:
  readoutPriority: async
  deviceClass: ophyd_devices.sim.sim_frameworks.StageCameraProxy
  deviceConfig:
    oav:
      signal_name: image
      ref_motors: [samx, samy]
  enabled: true
  readOnly: false

From the iPython BEC terminal run the following commands:
dev.oav.image_shape.set((204,144)).wait() (optional)
scans.grid_scan(dev.samx,-50,50,10,dev.samy,-50,50,10,relative=False)

Definition of Done

• Documentation is up-to-date.