Experimenting with more structured ways to handle command-line input/output in Rust

Refactor selectors test to not rely on funciton calls

Moves everything to a more rstest-style system of parameters, which is much cleaner than before.

Created by  finchie  on August 29, 2024
S2444K42FJFLTQMMU6PAVA4YRQGDNCMIFBQ5VO2LCD4GJ7LUCRYQC
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