Rewrite arg parsing in feather-proxy with argh 0.1

[Plecra]

Status

• Ready
• Development
• Hold

Description

This PR replaces the clap implementation with an equivalent (minus all clap's goodies :>) argh implementation.
This helps prune the dependency tree of a bunch of crates only clap is using, and reuses the argh dependency that is already being used by cargo-quill. (argh also shares dependencies with other crates in the tree like strum-macros and feather-blocks-generator)

Related issues

Leave empty if none

Checklist

• Ran cargo fmt, cargo clippy --all-targets, cargo build --release and cargo test and fixed any generated errors!
• Removed unnecessary commented out code
• Used specific traces (if you trace actions please specify the cause i.e. the player)

Note: if you locally don't get any errors, but GitHub Actions fails (especially at clippy) you might want to check your rust toolchain version. You can then feel free to fix these warnings/errors in your PR.