Steps to reproduce:
1. Create new Unity project
2. Install Entities package via Package Manager
3. Open Search window
4. In search field enter “TestSubScene”
5. Toggle Inspector Panel
6. Press on the kebab button next to “Open” button
7. From the menu select “Add Scene”
8. Observe the Console window

Actual results: “ArgumentException” error is thrown in the Console when selecting “Add Scene” from context menu
Expected results: “Add Scene” should be disabled/hidden when trying to select Scene or Asset which is located inside “Packages/“ directory or get a user-friendly warning that Scenes from packages can’t be opened

Reproducible with versions: 6000.0.73f1, 6000.3.13f1, 6000.4.3f1, 6000.5.0b4, 6000.6.0a2

Tested on (OS): macOS Silicon Tahoe 26.4

ArgumentException: Cannot open scene with path "Packages/com.unity.entities/Unity.Scenes.Hybrid.Tests/TestSceneWithSubScene/Subscene/TestSubScene.unity".
UnityEditor.SceneManagement.EditorSceneManager.OpenScene (System.String scenePath, UnityEditor.SceneManagement.OpenSceneMode mode) (at <df1951d9a0be44b1b591ff0cf7877633>:0)
UnityEditor.Search.Providers.AssetProvider+<>c.<CreateActionHandlers>b__57_6 (UnityEditor.Search.SearchItem item) (at /Users/bokken/build/output/unity/unity/Modules/QuickSearch/Editor/Providers/AssetProvider.cs:918)
UnityEditor.Search.SearchView.ExecuteAction (UnityEditor.Search.SearchAction action, UnityEditor.Search.SearchItem[] items, System.Boolean endSearch) (at /Users/bokken/build/output/unity/unity/Modules/QuickSearch/Editor/UITK/SearchView.cs:850)
UnityEditor.Search.SearchWindow.ExecuteAction (UnityEditor.Search.SearchAction action, UnityEditor.Search.SearchItem[] items, System.Boolean endSearch) (at /Users/bokken/build/output/unity/unity/Modules/QuickSearch/Editor/UITK/SearchWindow.cs:552)
UnityEditor.Search.SearchDetailView+<>c__DisplayClass41_1.<RefreshMoreMenu>b__1 () (at /Users/bokken/build/output/unity/unity/Modules/QuickSearch/Editor/UITK/SearchDetailView.cs:380)
UnityEditor.GenericMenu.CatchMenu (System.Object userData, System.String[] options, System.Int32 selected) (at /Users/bokken/build/output/unity/unity/Editor/Mono/GUI/GenericMenu.cs:164)