Franz-Xaver Salat

Results 2 issues of Franz-Xaver Salat

Probably not the most elegant way, but the fonts of the following sample-document are now correcly created and displayed. [example.pdf](https://github.com/user-attachments/files/20150109/example.pdf)

unchecked cast in descendantFont = (CompositeFont) library.getObject(descendantFontReference); produces a ClassCastException if object is a FontDescriptor. Handling for a FontDescriptor should be added