Forum improvements

What does this MR do?

Allows changing the title of threads. Also includes some refactoring and a simpler design for thread titles. The jump up / down button is now always accessible.

Sorry, I know this MR is not really a single coherent change - if it's not a huge problem I think we can keep it like this though since the changes all require rebuilding the thread top region.

How confident are you it won't break things if deployed?

confident

Links to related issues

https://foodsharing.de/?page=bezirk&bid=2296&sub=forum&tid=223759&pid=1284508#post-1284508

How to test

1. Checkout branch locally
2. Login as foodsaver
3. Go to a forum and play around. Jump up and down longer threads, change the title

Screenshots (if applicable)

Checklist

• added a test, or explain why one is not needed/possible...
• no unrelated changes
• asked someone for a code review
• set a "for:" label to indicate who will be affected by this change
• added to the next milestone (see https://gitlab.com/foodsharing-dev/foodsharing/-/milestones, unless it has a "for:Dev" label)
• added an entry to CHANGELOG.md
• added a short text in the release notes to /release-notes/YYYY-MM.md
• Once your MR has been merged, you are responsible to create a testing issue in the Beta Testing forum: https://foodsharing.de/?page=bezirk&bid=734&sub=forum. Please change the MRs label to "state:Beta testing".
  • Consider writing a detailed description in German.
  • Describe in a few sentences, what should be tested from a user perspective.
  • Also mention different settings (e.g. different browsers, roles, ...) how this change can be tested.
  • Be aware, that also non technical people should understand.