chore: improve air-gap-bundle messages

[ralgozino]

Summary 💡

Improve air-gap-bundle command help messages and instructions showed to the user.

Usage instructions where not pointing the user to the right flags to set.

Closes #734

Relates:

• feat: manage downloadable tools via a bundled mise (+ air-gapped bundle) #673

Description 📝

Creating an air-gap-bundle with the new feature printed the wrong instructions on how to use the bundle, misleading the user into a usage error.

This PR updates the logged instructions, help messages and aligns the terms used.

Breaking Changes 💔

None

Tests performed 🧪

• Tested bundle creation, then diff and apply using the bundle.

Future work 🔧

None

Self-assessment checklist 🏁

Important

Make sure that you completed this checklist before asking for review.

PRs that do not have this checklist ready won't be reviewed.

• My PR has a clear scope and does not mix together several unrelated changes
  - [ ] I've updated the docs/releases/unreleased.md file (or equivalent) I don't think is relevant to the release notes.
• I've tested the proposed changes and wrote the tests performed in the section above
• My branch is up-to-date with the target branch and there are no conflicts
• I've considered all the different cluster kinds (KFDDistribution, OnPremises, EKSCluster, Immutable) that may be affected by this change
• CI is green