Refactor encryption app commands

[fsamapoor]

Summary

I have made some adjustments to the apps/encryption/lib/Command classes to improve the code readability.

The improvements in this PR include but are not limited to:

• Using PHP8's constructor property promotion
• Adding return types
• Replacing return code integers with more readable strings.
• Using early returns

Checklist

• Code is properly formatted
• Sign-off message is added to all commits

[fsamapoor]

Conflicts resolved.

[nfebe]

Please, rebase this against latest master.

[fsamapoor]

Please, rebase this against latest master.

Done. But it has already got out-of-dated. Should I rebase it again?
I think we can wait for the second review for now.

[nfebe]

@fsamapoor thanks, all good! I was hoping CI might get green if you rebase but no, it's fine. Just wait for other reviews.

[fsamapoor]

@fenn-cs Cypress workflows are failing on almost all of my PRs. I don't know if there is anything that I can do to fix them.

[nfebe]

@fsamapoor Not to worry, those failures are unrelated (most likely as they are UI tests).

[fsamapoor]

Conflicts resolved.

[nfebe]

Conflicts resolved.

Thank you, please rebase.

[fsamapoor]

Thank you, please rebase.

Done.

[nfebe]

@fsamapoor now that this has another approval kindly, update/rebase it with master I would put my eyes on the jobs to get it in asap.

Thank you!

[fsamapoor]

@fsamapoor now that this has another approval kindly, update/rebase it with master I would put my eyes on the jobs to get it in asap.

Thank you!

Sure. Thank you! Other than Cypress workflows, I think there will be no issues.