Update version information in docs (+ minor other fixes)

[osnyx]

• update version references in docs for components, platform release, other references
• fix minor typos or phrasing
• pull in updated devhost docs
• gather noteworthy package (version) updates
• minor documentation for mailserver: ignore vmail user for garbage collection scan #1031

Note that this PR only contains information from the upstream NixOS changelog affecting one of our roles.
Other (breaking or noteworthy) changes are left for PL-132661.

PL-132670

@flyingcircusio/release-managers

Release process

Impact: -

Changelog: -

PR release workflow (internal)

• PR has internal ticket
• internal issue ID (PL-…) part of branch name
• internal issue ID mentioned in PR description text
• ticket is on 24.05 agile board
• ticket state set to Pull request ready
• if ticket is more urgent than within the next few days, directly contact a member of the Platform team

Design notes

• Provide a feature toggle if the change might need to be adjusted/reverted quickly depending on context. Consider whether the default should be on or off. Example: rate limiting.
• All customer-facing features and (NixOS) options need to be discoverable from documentation. Add or update relevant documentation such that hosted and guided customers can understand it as well.

Security implications

• Security requirements defined? (WHERE)
  • documentation needs to reflect the current state of the release
  • provide information about major version changes an breaking changes
  • availability: documentation still builds
• Security requirements tested? (EVIDENCE)
  • skimmed the build result of the docs

[dpausp]

re-check/update channel URLs after first release (also in release checklist)