feat: improve AI Chat UX, add notebook summary, and fix shared/reminders routing

memento-note/lib/i18n/LanguageProvider.tsx

@@ -31,15 +31,23 @@ export function LanguageProvider({ children, initialLanguage = 'en', initialTran
   initialLanguage?: SupportedLanguage
   initialTranslations?: Translations
 }) {
-  // Use server-provided initialLanguage for the first render to prevent hydration mismatch.
+  // Use server-provided initialLanguage and translations for the first render 
+  // to ensure client hydration matches server HTML exactly.
   const [language, setLanguageState] = useState<SupportedLanguage>(initialLanguage)
 
-  // Start with server-provided translations or English fallback
-  const [translations, setTranslations] = useState<Translations>(
-    (initialTranslations || enTranslations) as unknown as Translations
-  )
+  // Start with server-provided translations or fallback to English ONLY if it's the requested language
+  const [translations, setTranslations] = useState<Translations>(() => {
+    if (initialTranslations) return initialTranslations
+    return enTranslations as unknown as Translations
+  })
 
   const cacheRef = useRef<Map<SupportedLanguage, Translations>>(new Map())
+  
+  // Initialize cache with initial translations to prevent redundant loading
+  if (initialTranslations && !cacheRef.current.has(initialLanguage)) {
+    cacheRef.current.set(initialLanguage, initialTranslations)
+  }
+
   const isFirstRender = useRef(true)
 
   // Load saved preference from localStorage AFTER hydration
@@ -74,6 +82,7 @@ export function LanguageProvider({ children, initialLanguage = 'en', initialTran
   const setLanguage = useCallback((lang: SupportedLanguage) => {
     setLanguageState(lang)
     localStorage.setItem('user-language', lang)
+    document.cookie = `user-language=${lang};path=/;max-age=${60 * 60 * 24 * 365};samesite=lax`
     updateDocumentDirection(lang)
   }, [])