Nunito Sans and Bitter static UI instances

Sources downloaded from the Google Fonts repository:
https://github.com/google/fonts/blob/main/ofl/nunitosans/NunitoSans%5BYTLC%2Copsz%2Cwdth%2Cwght%5D.ttf
https://github.com/google/fonts/blob/main/ofl/bitter/Bitter%5Bwght%5D.ttf

NunitoSans-Regular.ttf: weight 400, optical size 20, other axes at their defaults.
NunitoSans-Bold.ttf: weight 700, optical size 20, other axes at their defaults.
Bitter-SemiBold.ttf: weight 600.
All variable axes were pinned with fontTools 4.59.0 (instantiateVariableFont).
These assets contain no fvar table; the game uses stb_truetype static font loading.

The source licenses are included in NunitoSans.OFL.txt and Bitter.OFL.txt.
The existing font assets and their licenses remain available as fallbacks.
