refactor(cli): 2x simplify migration to API client. See #2116

[alexec]

Checklist:

• Either (a) I've created an enhancement proposal and discussed it with the community, (b) this is a bug fix, or (c) this is a chore.
• The title of the PR is (a) conventional, (b) states what changed, and (c) suffixes the related issues number. E.g. "fix(controller): Updates such and such. Fixes #1234".
• I have written unit and/or e2e tests for my change. PRs without these are unlike to be merged.
• Optional. I've added My organization is added to the README.
• I've signed the CLA and required builds are green.

See #2116
I found myself copy-and-pasting lots of code from the CLI to server in other PRs. I kept thinking "I have 2 copies of the code", this PR reduces it to one copy.

[codecov]

Codecov Report

Merging #2290 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #2290   +/-   ##
=======================================
  Coverage   11.41%   11.41%           
=======================================
  Files          71       71           
  Lines       27899    27899           
=======================================
  Hits         3185     3185           
  Misses      24310    24310           
  Partials      404      404

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[whynowy]

LGTM