Please add a `FiberStatus` for fibres which have weird PSFs

PIPE2D-1677 reports that some fibres have strange PSFs, possibly due to dirt on the slit.

Please add a new `FiberStatus` to capture this.  It's tempting to use `DIRTY`, but let's describe the symptoms not the hypothesis.  So I propose `BAD_PSF`.

This'll need to be in datamodel.txt, but also to be added to the enums, and set for appropriate fibres in the pfsDesign files.