Fix e2e tests: Set English language before navigation

- Add context.addInitScript in beforeEach hooks to set English locale before page navigation
- Remove debugging code from useLanguage hook
- Remove unused setup file imports
- Fix exchange test to check for English text correctly
- All frontend tests passing

frontend/e2e/profile.spec.ts

@@ -70,7 +70,13 @@ async function clearProfileData(page: Page) {
 }
 
 test.describe("Profile - Regular User Access", () => {
-  test.beforeEach(async ({ page }) => {
+  test.beforeEach(async ({ context, page }) => {
+    // Set English language before any navigation
+    await context.addInitScript(() => {
+      if (typeof window !== "undefined") {
+        window.localStorage.setItem("arbret-locale", "en");
+      }
+    });
     await clearAuth(page);
     await loginUser(page, REGULAR_USER.email, REGULAR_USER.password);
   });