fix: clippy errors and small typos in write function

[gabyx]

Proposed Changes

• Make all clippy warnings errors.
• Correct write functions.

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• A new feature (non-breaking change which adds functionality).
• A breaking change (fix or feature that would cause existing
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Further Comments

[cmdoret]

question: is there any issues with having input as positional argument? i.e.

index data.nt
instead of
index -i input.nt

Also this would set -i as the short option, which kind of clashes with index in pseudo -i

[gabyx]

ah jeah. that might be better. Make --input and --index. I am anyway not a big fan of using abreviations.
or -i and -x for index. @cmdoret : can you do a PR on this?