"Export" menu item appears active in Project window while "Export Package..." and "Export Assets..." sub-menu options are disabled

Steps to reproduce:

Case 1:

1. Create a Unity project
2. Go to a "Project" window
3. Select "Burst" package
4. Right-click and select "Export", which is displayed as active
5. Observe the result

Case 2:

1. Create a Unity project
2. Go to a "Project" window
3. Select "Packages"
4. Right-click and select "Create UPM Package..."
5. Enter the package name "Test" and click the "Create" button
6. Create one more custom "Test2" package in the same way
7. Return to a "Project" window
8. Find newly created "Test" and "Test2" packages
9. Select them both
10. Right-click and select "Export"
11. Observe the result

Actual results: "Export" menu item is displayed as active, though both sub-menu options "Export Package..." and "Export Assets..." are displayed as disabled

Expected results:  "Export" menu item should be displayed as disabled because there is nothing to export

Reproducible with versions: 6000.5.0a7

Not reproducible with versions: 6000.5.0a6, as the group export function landed just in the 6000.5.0a7 build

Tested on (OS): macOS - Tahoe 26.3

Notes: "Export" menu item is displayed as active for the multiple packages selection. It should be disabled too.