feat: Add EU cookie banner and user settings page

Cookie Banner:
- GDPR-compliant consent banner
- Shows on first visit, stores consent in localStorage
- Two options: Accept All / Only Essential
- Dark theme with smooth animations

Settings Page (/settings):
- Profile form: display name editing
- Password change with validation
- Cookie settings info section
- Privacy links and account info

New files:
- src/hooks/useCookieConsent.ts
- src/components/CookieBanner.tsx
- src/components/ProfileForm.tsx
- src/components/PasswordChangeForm.tsx
- src/services/profile-actions.ts
- src/app/settings/page.tsx

src/app/layout.tsx

@@ -10,6 +10,7 @@ import ActiveSessionBanner from "@/components/ActiveSessionBanner";
 import MainContentWrapper from "@/components/MainContentWrapper";
 import AuthListener from "@/components/AuthListener";
 import SyncHandler from "@/components/SyncHandler";
+import CookieBanner from "@/components/CookieBanner";
 
 const inter = Inter({ subsets: ["latin"], variable: '--font-inter' });
 
@@ -56,6 +57,7 @@ export default function RootLayout({
                             <UploadQueue />
                             {children}
                         </MainContentWrapper>
+                        <CookieBanner />
                     </SessionProvider>
                 </I18nProvider>
             </body>