Filter browse list by works containing fingerings

[craigsapp]

On the browse page there are various filters for selecting works that have lyrics, figured-bass, IIIF encodings and manual modernization filtering. Also add a filter for listing works that contain fingerings:

F is used for figured bass already, so maybe use G for fingerings.

This will involve adding metadata about fingerings on the data server.

Here is an example of a work with fingerings:

https://polishscores.org/?id=pl-wtm--iii-41-637-1--001-001