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/mods/core/localizations/en.jsonc

@@ -62,6 +62,16 @@
   "Geography": "Geography",
   "Informatics": "Informatics",
   "ForeignLanguage": "Foreign language",
+  "English": "English",
+  "German": "German",
+  "BelarusianLanguage": "Belarusian",
+  "UkrainianLanguage": "Ukrainian",
+  "Communication": "Communication",
+  "Pedagogy": "Pedagogy",
+  "Medicine": "Medicine",
+  "Cooking": "Cooking",
+  "Administration": "Administration",
+  "Librarianship": "Librarianship",
   "Agility": "Agility",
   "Strength": "Strength",
   "Endurance": "Endurance",