confusing branch names

[anemochore]

While v2 is out of the question, readme says main is 'clap v4 derive pattern' and clap_v4_builder is 'clap v4 builder pattern'. But actual branches are more than that: main, clap_v4_builder, clap_v4_derive, and clap v4.

If readme is correct, what are these other branches? It's confusing. I think it'll be more helpful to readers to cut down branches (or at least update readme).