Overhaul key command

[dtrudg]

Type of issue
technical debt

Description of issue
The implementation of the key command has some significant technical debt, with portions of code at a different level than they should be. In addition, management of keys is not trivial for those not clear about the public/private nature, fingerprints etc. of GPG. More expressive CLI output, and re-examining of the verbs and flags would be useful.

[dtrudg]

Will close this now. While we havent perhaps overhauled as much as was first talked about in 2021, we....

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