[Preview] How to handle unsaved changes implementation
## Bug report

### Required System information

Enterprise Edition
WSL and Mac
Local

### Describe the bug

For now, [Open preview] button is clickable but generates a warning message of content being lost if confirming (see video).
Or, it has been discussed that, when changes are made but not saved, [Open Preview] button should be disabled and a hovering tooltip indicating the user to save changes before opening preview.

### Steps to reproduce the behavior

1. Go to CM, on the Edit view of an entry
2. Do some changes and DO NOT save
3. Check [Open preview] button is clickable (should not be), grayed on IOS, not even grayed on Windows
4. Click on [Open preview] and check the warning message

### Expected behavior

: no clickable button, hovering tooltip to save changes

### Screenshots


https://github.com/user-attachments/assets/73c77674-afe7-4e30-8206-3fddd1e018bf


