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/Api/SchoolEndpoints.cs

@@ -54,6 +54,7 @@ internal static class SchoolEndpoints
                 request.ModIds,
                 request.Map,
                 request.NameSetId,
+                request.NativeLanguage,
                 NewCompletion<SchoolCreationOutcome>());
             commands.Enqueue(command);
 
@@ -77,6 +78,8 @@ internal static class SchoolEndpoints
                     Problem(StatusCodes.Status400BadRequest, "invalid-catalog", "The selected packs could not be loaded."),
                 SchoolCreationError.UnknownNameSet =>
                     Problem(StatusCodes.Status400BadRequest, "unknown-name-set", "The selected name set is not in the catalog."),
+                SchoolCreationError.UnknownNativeLanguage =>
+                    Problem(StatusCodes.Status400BadRequest, "unknown-native-language", "The selected native language is not in that name set."),
                 _ => Results.Problem("Unknown error."),
             };
         })
@@ -486,7 +489,8 @@ internal sealed record CreateSchoolRequest(
     DateTime StartDate,
     IReadOnlyList<string>? ModIds,
     MapLayout? Map,
-    string? NameSetId);
+    string? NameSetId,
+    string? NativeLanguage);
 
 internal sealed record SchoolResponse(int Id, string Name, DateTime GameTime, bool Running, byte SpeedIndex)
 {