Add contact, privacy, and terms pages with localization support

- Implemented contact page with form submission functionality and email integration.
- Created privacy and terms pages with structured content and localization.
- Updated English and French localization files to include new strings for contact, privacy, and terms.
- Enhanced About page with detailed sections on mission, technology, security, and tools offered.

frontend/src/App.tsx

@@ -14,6 +14,7 @@ const AboutPage = lazy(() => import('@/pages/AboutPage'));
 const PrivacyPage = lazy(() => import('@/pages/PrivacyPage'));
 const NotFoundPage = lazy(() => import('@/pages/NotFoundPage'));
 const TermsPage = lazy(() => import('@/pages/TermsPage'));
+const ContactPage = lazy(() => import('@/pages/ContactPage'));
 const AccountPage = lazy(() => import('@/pages/AccountPage'));
 const ForgotPasswordPage = lazy(() => import('@/pages/ForgotPasswordPage'));
 const ResetPasswordPage = lazy(() => import('@/pages/ResetPasswordPage'));
@@ -90,6 +91,7 @@ export default function App() {
             <Route path="/reset-password" element={<ResetPasswordPage />} />
             <Route path="/privacy" element={<PrivacyPage />} />
             <Route path="/terms" element={<TermsPage />} />
+            <Route path="/contact" element={<ContactPage />} />
 
             {/* PDF Tools */}
             <Route path="/tools/pdf-to-word" element={<ToolLandingPage slug="pdf-to-word"><PdfToWord /></ToolLandingPage>} />