fix: App hanging when changing passcode on iOS

- Add 300ms delay between authentication and passcode change modals
- Add try-catch to handle authentication cancellation gracefully
- Prevents iOS UI thread hang when two modals open back-to-back

Fixes #6313

Author: DSingh0304

app/views/ScreenLockConfigView.tsx

@@ -132,7 +132,15 @@ class ScreenLockConfigView extends React.Component<IScreenLockConfigViewProps, I
 	changePasscode = async ({ force }: { force: boolean }) => {
 		const { autoLock } = this.state;
 		if (autoLock) {
-			await handleLocalAuthentication(true);
+			try {
+				await handleLocalAuthentication(true);
+				// Add a small delay to ensure the first modal is fully closed before opening the next one
+				// This prevents the app from hanging on iOS when two modals open back-to-back
+				await new Promise(resolve => setTimeout(resolve, 300));
+			} catch {
+				// User cancelled or authentication failed
+				return;
+			}
 		}
 		logEvent(events.SLC_CHANGE_PASSCODE);
 		await changePasscode({ force });

app/views/SecurityPrivacyView.tsx

@@ -59,7 +59,14 @@ const SecurityPrivacyView = ({ navigation }: ISecurityPrivacyViewProps): JSX.Ele
 
 	const navigateToScreenLockConfigView = async () => {
 		if (server?.autoLock) {
-			await handleLocalAuthentication(true);
+			try {
+				await handleLocalAuthentication(true);
+				// Add a small delay to prevent modal conflicts on iOS
+				await new Promise(resolve => setTimeout(resolve, 300));
+			} catch {
+				// User cancelled or authentication failed
+				return;
+			}
 		}
 		navigateToScreen('ScreenLockConfigView');
 	};