*: make generation configurable, use sdkconfig defaults
This moves badge hardware generation selection over from a header file into ESP-IDF configuratbility.
The generaiton can now be selected by specifying BADGE_GENERATION
or
-g
when running the initial built.
In addition, each generation now gets its own sdkconfig.defaults file (instead named sdkconfig.$generation) and the big autogeneration sdkconfig file gets yeeted.