Enhance school creation and staffing management with native language support

- Updated protocol documentation to include `nativeLanguages` in `nameSets` and added `nativeLanguage` to school creation options.
- Enhanced the UI for school creation to allow selection of native languages, improving user experience.
- Revised API interfaces to accommodate new native language features, ensuring proper data handling.
- Improved localization strings to support new native language functionalities in both English and Russian.
- Updated tests to validate the new native language features and ensure robust functionality in staffing scenarios.

src/HSchool.Server/Game/SchoolStore.cs

@@ -28,6 +28,8 @@ internal sealed class SchoolSave
 
     public string? NameSetId { get; init; }
 
+    public string? NativeLanguage { get; init; }
+
     public IReadOnlyList<PresenceSnapshot>? Presence { get; init; }
 }
 
@@ -162,6 +164,7 @@ internal sealed class SchoolStore
                     ModIds = save.ModIds,
                     Map = save.Map,
                     NameSetId = save.NameSetId,
+                    NativeLanguage = save.NativeLanguage,
                     Presence = save.Presence,
                 });
             }