refactor: Replace hardcoded monospace font with AppTypography constant

- Updated multiple instances of the 'monospace' font family to use AppTypography.monospaceFontFamily for consistency across the application.
- This change enhances maintainability and ensures a unified typography approach throughout the app.

lib/features/auth/views/authentication_page.dart

@@ -288,7 +288,7 @@ class _AuthenticationPageState extends ConsumerState<AuthenticationPage> {
                   hostText,
                   style: context.conduitTheme.bodySmall?.copyWith(
                     color: context.conduitTheme.textSecondary,
-                    fontFamily: 'monospace',
+                    fontFamily: AppTypography.monospaceFontFamily,
                   ),
                 ),
               ],