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

Rename `parse` module to `parse_fluent`

Since the term parse is ambiguous in a project that parses both rust & fluent files, this makes things much clearer. Many of the functions also had the match_ prefix stripped as it was unhelpful boilerplate.

Created by  finchie  on February 14, 2024
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