Phase 4: Translate Shared Components - common, navigation, status labels

- Translate LoadingState and EmptyState components (common namespace)
- Translate Header navigation labels (navigation namespace)
- Translate StatusBadge trade status labels (exchange namespace)
- Create navigation.json translation files for es, en, ca
- Create exchange.json translation files for status/direction/transfer labels
- Update IntlProvider to load navigation and exchange namespaces
- Update frontend tests to expect Spanish translations (default language)
- Configure Playwright to use English language for e2e tests via storageState
- Fix test expectations to match translated strings

All frontend and e2e tests passing.

frontend/locales/ca/exchange.json

@@ -0,0 +1,17 @@
+{
+  "status": {
+    "pending": "Pendent",
+    "completed": "Completada",
+    "userCancelled": "Cancel·lada per Usuari",
+    "adminCancelled": "Cancel·lada per Admin",
+    "noShow": "No Present"
+  },
+  "direction": {
+    "buy": "COMPRAR BTC",
+    "sell": "VENDRE BTC"
+  },
+  "transferMethod": {
+    "onchain": "Onchain",
+    "lightning": "Lightning"
+  }
+}