Remove local file imports

What does this MR do and why?

• Remove local imports to resolve arbitrary file issues with import.

• Resolves https://gitlab.com/crafty-controller/crafty-4/-/issues/649

• Resolves #519 (closed)

• Confirm traversal checking through import process

• Tidy up loading message when gathering files from archive

• Check what happens if a user uploads a tar

• Check to see if !937 (merged) is merged for scope creep "send_error" refactor

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MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• Have you checked this doesn't interfere/conflict/duplicate someone elses work?
• Have you fully tested your changes?
• Have you resolved any lint issues?
• Have you assigned a reviewer?
• Have you applied correct labels?