[stable8] fix(NcAppContent): don't remove list when showing details in mobile or no-split mode

[wofferl]

☑️ Resolves

• Fix [NcAppContent] list is rebuild every time when details were shown with no-split or mobile view #6204

As mentioned in #6204 the change in 8.10.0 causes the item list to rebuild every time the details of an item are shown.
With a dynamic list like in the news app, where read items are removed from the list when refreshing it, this means that the selected item you looked at the details are gone immediately when you close the details.
It also affects the performance, because of the rebuilding when closing the details, which is notable on mobile devices.

I think there is no technical reason to delete it, so it is better to just hide the list.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Please upload report for BASE (stable8@0d00038). Learn more about missing BASE report.

Additional details and impacted files

@@            Coverage Diff             @@
##             stable8    #6261   +/-   ##
==========================================
  Coverage           ?   43.11%           
==========================================
  Files              ?      161           
  Lines              ?     4112           
  Branches           ?     1070           
==========================================
  Hits               ?     1773           
  Misses             ?     2220           
  Partials           ?      119           

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

[wofferl]

@GretaD @ShGKme Is there any information on this problem, whether the old behavior should be restored or whether it will remain as it is in the future.

[GretaD]

hi, sorry for the late reply, i wrote on our frontend talk room, so more people are involved to get a decision.

[susnux]

Makes sense from my view. but should be checked with mail

[susnux]

/backport to main