docs: keep release instructions accurate and easy to follow

[PatrickSys]

Some setup pages still called the release a preview and described an ineffective NestJS switch.
The wording now matches the shipped analyzers and Node requirement, and clearly labels older setup checks.
The existing page layout stays the same.
Tested: the new wording regression failed first, then all release-wording tests passed; build and full tests also run before pushing.

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-10-16T18:09:42.443961Z	3eb86fd	PR opened

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[greptile-apps]

Confidence Score: 5/5

[Low impact] The PR appears safe to merge.

Summary

Updates release and setup wording without changing runtime behavior.

• Setup guides explain the 2.4.0 release and how its checks were done.
• The release guides show NestJS as an automatically detected analyzer.

No actionable issues found. Review checks were based on source inspection; tests were not run.

_{Reviews (1) · Last reviewed commit: "docs: align release wording with the cur..." · Reviewed by Greptile}