Font fallback support is incomplete

[RattlebonesJones]

Is your feature request related to a problem? Please describe.

Currently 'typeface' in config\fonts.json allows you to specify a fallback font to use if the main font lacks a character, as per #36326. 'map_typeface' and 'overmap_typeface', however, do not. This is an issue for non-english users using fonts other than Unifont, as well as for mods that add buildings with unicode characters.

Describe the solution you'd like

For 'map_typeface' and 'overmap_typeface' to support fallback fonts.