tcld docs gen

[prasek]

What was changed

• Added tcld docs gen for Nexus commands
• Added docs gen for other tcld commands (Experimental)
  • some sync with published docs is needed to align the two

See related

• https://github.com/temporalio/documentation/pull/3151
• https://github.com/temporalio/cli/pull/693

Why?

Needed to create nexus.mdx and wanted to use docs gen

Checklist

1. How was this tested:

• go run ./app/internal/cmd/gen-docs
• copied generated nexus.mdx to temporalio/documentation
• yarn start
• verified via http://localhost:3000/

2. Any docs updates needed?

• https://github.com/temporalio/documentation/pull/3151

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1 out of 2 committers have signed the CLA.

:white_check_mark: prasek
:x: david049
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[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.
_{You have signed the CLA already but the status is still pending? Let us recheck it.}