docs(web-modeler): update Web Modeler logging docs

[pablocabrera85]

Description

Closes https://github.com/camunda/web-modeler/issues/18704

When should this change go live?

• This is a bug fix, security concern, or something that needs urgent release support. (add bug or support label)
• This is already available but undocumented and should be released within a week. (add available & undocumented label)
• This is on a specific schedule and the assignee will coordinate a release with the Documentation team. (create draft PR and/or add hold label)
• This is part of a scheduled alpha or minor. (add alpha or minor label)
• There is no urgency with this change (add low prio label)

PR Checklist

• The commit history of this PR is cleaned up, using {type}(scope): {description} commit message(s)

• My changes are for an upcoming minor release and are in the /docs directory (version 8.9).
• My changes are for an already released minor and are in a /versioned_docs directory.

• I added a DRI, team, or delegate as a reviewer for technical accuracy and grammar/style:
  • Engineering team review
  • Technical writer review via @camunda/tech-writers unless working with an embedded writer.

[github-actions]

👋 🤖 🤔 Hello, @pablocabrera85! Did you make your changes in all the right places?

These files were changed only in docs/. You might want to duplicate these changes in versioned_docs/version-8.8/.

• docs/reference/announcements-release-notes/890/890-announcements.md
• docs/reference/announcements-release-notes/890/890-release-notes.md
• docs/reference/announcements-release-notes/890/whats-new-in-89.md
• docs/self-managed/components/components-upgrade/880-to-890.md
• docs/self-managed/components/components-upgrade/introduction.md
• docs/self-managed/components/modeler/web-modeler/configuration/configuration.md
• docs/self-managed/components/modeler/web-modeler/configuration/logging.md
• docs/self-managed/update/administrators/overview.md

You may have done this intentionally, but we wanted to point it out in case you didn't. You can read more about the versioning within our docs in our documentation guidelines.

[mesellings]

@afgambin could you give these a review please? 🙏

[Copilot]

Pull Request Overview

This PR updates the Web Modeler documentation to reflect the migration from Logback to Apache Log4j 2 logging framework in version 8.9, and updates version references across documentation from 8.8 to 8.9.

Key changes:

• Updates Web Modeler logging documentation with Log4j2 configuration and examples
• Adds version 8.9 upgrade guides and release documentation
• Updates version references from 8.8 to 8.9 across administrator and component upgrade guides

Reviewed Changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
sidebars.js	Adds whats-new-in-89 page to version 8.9.0 announcements sidebar
docs/self-managed/update/administrators/overview.md	Updates version references from 8.8 to 8.9 and related links
docs/self-managed/components/modeler/web-modeler/configuration/logging.md	Updates logging framework from Logback to Log4j2, adds default configuration example and environment variables documentation
docs/self-managed/components/modeler/web-modeler/configuration/configuration.md	Updates logging configuration table with Log4j2 variables and corrected file path
docs/self-managed/components/components-upgrade/introduction.md	Adds upgrade sections for 8.8 to 8.9 and 8.7 to 8.8
docs/self-managed/components/components-upgrade/880-to-890.md	New upgrade guide documenting the logging framework change
docs/reference/announcements-release-notes/890/whats-new-in-89.md	New page describing what's changed in version 8.9
docs/reference/announcements-release-notes/890/890-release-notes.md	Adds alpha2 release notes for logging framework changes
docs/reference/announcements-release-notes/890/890-announcements.md	Adds breaking change announcement for logging framework migration

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[afgambin]

These two GH links do not work, is that on purpose? maybe they do not exist just yet?

[pablocabrera85]

No, they do not exists, but since I had to document the changes for 8.9.0-alpha2 the page, I added that 😄

[afgambin]

The linked guide seems to be for upgrading to 8.8, not to 8.9 as supposed (I believe)

[pablocabrera85]

Yes. I'm assuming that this page will be updated when 8.9 is released. Maybe something to take into account when adding a new minor, some pages could be cleaned up in preparation for the content associated with that release.

[afgambin]

Oh, I see… I’m not really in favor of linking to something assuming it will be updated later. I’d rather update the link (e.g., on this page) when the referenced page is updated as well - ideally in the same PR. Otherwise, it may be forgotten. Anyhow, I leave it up to @mesellings's pass.

[afgambin]

I made some text tweaks directly and left some comments for you to address. Nice work!

[mesellings]

@pablocabrera85 @afgambin I'll review this for the What's new in 8.9 work, I wasn't planning on adding that page in yet, so I'd like to give that a once over first 👍

[mesellings]

Thanks for your work here @pablocabrera85 - we might not include this in the 8.9 What's new page as we move towards 8.9 as this is meant to be a soft intro to the main features (supported by announcements and release notes for granular info) but happy for it to be there as is for now the work has been done in this PR - approved from my end from that perspective - when do you want this merged and released?

[pablocabrera85]

@mesellings Would it be possible to merge it today as it is, or do you need me to remove the 8.9 What's new page changes?
I believe this should be released when we release the 8.9.0-alpha2. Should we wait to have this merged until then?

How do we usually handle this kind of changes in the docs bound to a release that is not yet available?

[mesellings]

Hi @pablocabrera85 no we can leave the what's new page in, that's fine - alpha docs are a wip so this is fine - regarding the feature, it often depends really - we can hold off releasing until the day before the release if there is a critical reason why we should wait until the feature is merged, or we can just release now/in anticipation of the release - this looks more like the latter, but it's up to you if there's a reason to hold the docs back?

[pablocabrera85]

I don't think there is a reason to hold back. I'll proceed with merging it then 👍 @wollefitz Do you see any reason not to release this now after merging?