Zwiefalten, D-Ka Aug. LX: Proof folio mapping

Couple of issues here:
-Folio 001b is mapped to the image for what should presumably be called 001a; this makes all the folios off by one from their images for much of the MS
-A section in the middle, between folios 103v and 104r, is added and numbered separately, as a001r-a037v. (There is also a 38th, blank, folio, which has no chant records.) In the index, all of this ends up at the end, so the information for this added section is somewhere after that for folio 237r. As is, the records keep going, so that after one emerges from the added section the images are paired with information about chants 38.5 folios away.
-After (the image of) 192v, there is a strip of parchment with the end of a chant (apparently unnumbered). This will need a "no new chant records begin here" placeholder for both recto and verso, otherwise the records get off by another folio's worth.
-For some reason, there is no folio 232, either image or chant records--it just got skipped in the numbering. This shouldn't matter once the other chants are aligned, but at the moment it creates another off-by-one issue until the place the real 232 would be, so it's worth being aware of. Similarly, the final chant of the book (on 237v) seems to have no Cantus record at the moment, so this page will have no record even after the rest of the mapping is corrected.

-The chant information for 230r won't load for me. 229v and 230v--fine. 230r: nada. Why this page? A mystery.

Start by reproducing the missing chant information for folio 230r and compare it with 229v and 230v. Then trace the folio-to-image and chant-record mapping described for the added a001 section, the parchment after 192v, folio 232, and final folio 237v. Done means the affected images and chant records remain aligned and 230r loads.

Written by the indexing model from the issue text.