fix(Preview): hide link bubble when preview menu opens

[max-nextcloud]

📝 Summary

• Only show link bubble when cursor is inside the link. This way it does not show when opening the preview menu (which moves the cursor to the start of the line).
• Part of Link preview follow up #5442 .

🏁 Checklist

• Code is properly formatted (npm run lint / npm run stylelint / composer run cs:check)
• Sign-off message is added to all commits
• Tests (unit, integration and/or end-to-end) passing and the changes are covered with tests
• Documentation is not required

[max-nextcloud]

failing tests are related. They expect the bubble to show when cursor is on first char.