Document SDK generation process and rollout steps

[Flo4604]

Capture the current SDK generation workflow and where to run it.

• To force-generate SDKs, go to the GitHub Actions in the sdks repo and run the generate workflows via the Run workflow button.
• The workflows will open PRs; merge them. You may need to run generation multiple times to resolve merge conflicts.
• Once merged, the packages will publish themselves.
• SDKs pull the OpenAPI spec from main, so generation can happen as soon as the spec change is merged.

Links:

• sdks Actions: https://github.com/unkeyed/sdks/actions

[linear[bot]]

ENG-2210