adjust fallback font styles to better handle missing characters

[rlskoeser]

articles in the scribes issues include characters that are not in our fonts; we need to improve the fallback font styles so the size mismatch is not so obvious

Use the font style matcher https://meowni.ca/font-style-matcher/
to determine the best size for fallback fonts to match the primary font

Then declare fallback fonts locally with size overrides — see example here
Princeton-CDH/geniza#555