Incorrect code generation for .frac

[RecursiveError]

#2
The .frac type is meant to be semantic only — in essence, it should behave the same as a conventional .source.
Currently, the code generator produces fractional as if it were .source, instead of generating it as .frac.

generate.zig — see:
https://github.com/RecursiveError/ClockHelper-zig/blob/75ceb2607919f590544589ab52b69c423929599e/generate.zig#L476C1-L476C38

Possible fixes

1. Remove the .frac type entirely (if redundant).
2. Add proper code generation support so that fractional is emitted under .frac instead of .source.