Tidy up chargen finalization

Three effects, in order of importance:

1. Remove a bug that allowed nameless characters to be created, causing debug message spam and probably breaking saves. (repro steps on old build: answer "yes" when asked if you want to waste points, then "no" when asked if you want to accept a random name)

2. Make it so that an empty name field doesn't effectively no-op the question about wasting leftover points.

3. Make the code tidier.