Currently, when running a bluesky XRC beamsize is being put in ispyb as 80x20 e.g.

This is incorrect, the real beamsize can be read from the transfocator, specifically BL04I-MO-FSWT-01:VER and BL04I-MO-FSWT-01:HOR. We should read these during collection and put the data into ispyb. I03 does not have a transfocator and so they should use the beamsize as currently calculated.

Acceptance Criteria

• Beamsize is read from the above PVs on i04
• This is what is put into ispyb
• Behaviour on i03 is unchanged