[8.x](backport #4362) Deprecate the Logs Stream app

[mergify]

Description

Logs Stream is being deactivated by default. This PR addresses that, deemphasizes Logs Stream as a way to view and manage logs, but also includes instructions on activating Logs Stream if users do still want to use it.

Documentation sets edited in this PR

Check all that apply.

• Stateful (docs/en/observability/*)

Related issue

Closes #4315

Checklist

• Product/Engineering Review
• Writer Review

Follow-up tasks

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• This PR does not need to be ported to another doc set because:
  • The concepts in this PR only apply to one doc set (serverless or stateful)

---

This is an automatic backport of pull request #4362 done by [Mergify](https://mergify.com).

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