Steps to reproduce

1. Ensure that the QML Language Server is enabled in Qt Creator
2. Create a new Qt Quick Application, using a Qt 6.8.4 kit
3. Click on the Language Server tool button and verify that qmlls 6.8.4 is active
4. Go to Projects mode. Add (and switch to) a Qt 6.10.0 kit
5. Click on the Language Server tool button again

Expected Outcomes
After the last step, qmlls 6.10.0 is now active

Actual Outcomes

• After the last step, qmlls 6.8.4 is still active.
• Clicking "Inspect Language Clients" shows that qmlls 6.10.0 has been initialized, but it is not active and we're not able to select it.
• We need to close and re-open the *.qml file for the version switch to take effect