fix(i18n): localize application workflows

Use stable checklist and interview keys for system copy while preserving user-authored content. Localize creation-tab errors, language selectors, match bands, dates, and selected-CV context.

job-tracker-ui/src/interview-prep.test.tsx

@@ -57,7 +57,21 @@ function routeGet(overrides: Record<string, any> = {}) {
   });
 }
 
-beforeEach(() => jest.clearAllMocks());
+beforeEach(() => {
+  jest.clearAllMocks();
+  window.localStorage.setItem("uiLanguage", "en");
+});
+
+test("localizes interview categories while preserving user-authored preparation", async () => {
+  window.localStorage.setItem("uiLanguage", "nb");
+  routeGet();
+
+  render(<ApplicationInterviewPrep jobId={7} />);
+
+  expect((await screen.findAllByText("Selskapsresearch")).length).toBeGreaterThan(0);
+  expect(screen.getAllByText("Atferdsbaserte spørsmål").length).toBeGreaterThan(0);
+  expect(screen.getByText("Funding history")).toBeInTheDocument();
+});
 
 test("prep renders grouped items with progress and marks AI-sourced ones", async () => {
   routeGet();