fix: render Ref-compatible GUI display names

app/game-api/test/gameDisplayNames.test.ts

@@ -0,0 +1,32 @@
+import { describe, expect, it } from 'vitest';
+
+import {
+    resolveCityLevelName,
+    resolveDedicationLevelName,
+    resolveNationLevelName,
+    resolveOfficerLevelName,
+    resolveRegionName,
+    sanitizeInternalDisplayCode,
+} from '../src/services/gameDisplayNames.js';
+
+describe('Ref GUI display names', () => {
+    it('maps nation, city, region, office, and dedication levels to Ref labels', () => {
+        expect(resolveNationLevelName(3)).toBe('주자사');
+        expect(resolveCityLevelName(8)).toBe('특');
+        expect(resolveRegionName(2)).toBe('중원');
+        expect(resolveOfficerLevelName(9, 3)).toBe('간의대부');
+        expect(resolveOfficerLevelName(5, 3)).toBe('-');
+        expect(resolveOfficerLevelName(5)).toBe('제3모사');
+        expect(resolveDedicationLevelName(2, 30)).toBe('29품관');
+        expect(resolveDedicationLevelName(0, 30)).toBe('무품관');
+    });
+
+    it('never exposes internal prefixes or numeric fallback codes', () => {
+        expect(sanitizeInternalDisplayCode('che_event_의병')).toBe('의병');
+        expect(sanitizeInternalDisplayCode('che_법가')).toBe('법가');
+        expect(sanitizeInternalDisplayCode('3')).toBe('-');
+        expect(resolveNationLevelName(99)).toBe('-');
+        expect(resolveCityLevelName(99)).toBe('-');
+        expect(resolveRegionName(99)).toBe('-');
+    });
+});