fix(i18n): retain historical checklist text for unknown system keys

job-tracker-ui/src/checklist-translation-token.test.ts

@@ -0,0 +1,11 @@
+import { checklistSystemTranslationToken } from './applicationWorkspace';
+
+test.each(['retired-system-task', 'constructor', '__proto__'])('does not manufacture translation keys for %s', key => {
+  expect(checklistSystemTranslationToken(key)).toBeNull();
+});
+
+test('retains the known system translation and learning/custom boundaries', () => {
+  expect(checklistSystemTranslationToken('prepare-cv')).toBe('prepareCv');
+  expect(checklistSystemTranslationToken('learning:prepare-cv')).toBeNull();
+  expect(checklistSystemTranslationToken(null)).toBeNull();
+});