feat: collaborative description editing

[grnd-alt]

• Target version: main

Summary

collaborative editing of the description.
requires: nextcloud/text#9062

TODO

• text's last saved indicator says 57 years ago
• old description saving mechanism still interfering
• another user updated description notification pops up when notify_push is on
• conflict view (needed/possible?)
• attachments (requires text, see text pr) ⚠️ postponed
• cypress failures

Checklist

• Code is properly formatted
• Sign-off message is added to all commits
• Tests (unit, integration, api and/or acceptance) are included
• Documentation (manuals or wiki) has been updated or is not required

[github-actions]

🐢 Performance warning.
It looks like the query count of the integration tests increased with this PR.
Database query count is now 200687 was 198420 (+1.14%)
Please check your code again. If you added a new test this can be expected and the base value in tests/integration/base-query-count.txt can be increased.

[github-actions]

🐢 Performance warning.
It looks like the query count of the integration tests increased with this PR.
Database query count is now 202839 was 198420 (+2.22%)
Please check your code again. If you added a new test this can be expected and the base value in tests/integration/base-query-count.txt can be increased.

[github-actions]

🐢 Performance warning.
It looks like the query count of the integration tests increased with this PR.
Database query count is now 202734 was 198420 (+2.17%)
Please check your code again. If you added a new test this can be expected and the base value in tests/integration/base-query-count.txt can be increased.