Small fixes: Andor binning, diSPIM slope units, button reset, SCAPE hook guard

[bls337]

• Andor binning reads its property name from its own class instead of the PCO class. It's the same string, so behavior doesn't change.
• The diSPIM sheet width slope label now shows "m°/px", matching how the value is used and how 1.4 labelled it. It showed "μ°/px".
• A duplicate add of the slope value label is removed from the calibration panel.
• The acquisition buttons are reset after a run with invokeLater instead of invokeAndWait, since nothing waited on the result.
• The SCAPE after-camera hook now checks that the controller exists before triggering it, as the diSPIM hook does. A run with a DemoCamera and PLogic devices no longer stops silently on a NullPointerException.