feat: scaffold ShieldAI React Native mobile app MVP (FRE-4572)

Build complete Expo/React Native mobile app with:
- Auth flow: email/password login, registration, biometric auth
- Dashboard: exposure summary, spam stats, voice protection status
- DarkWatch: watch list management, exposure feed, alert toggles
- SpamShield: call/text history, whitelist/blacklist management
- VoicePrint: family member enrollment, voice analysis
- Settings: tier management, notification preferences, security
- Push notification integration via FCM/APNs
- Offline-first state management with Zustand + AsyncStorage
- Integration with @shieldai/mobile-api-client for API services
- React Navigation with auth-aware routing (stack + bottom tabs)
- Dark theme with consistent design system (colors, spacing, typography)
- Network status monitoring and offline request queuing

Co-Authored-By: Paperclip <noreply@paperclip.ing>

packages/mobile/src/components/Input.tsx

@@ -0,0 +1,51 @@
+import React from 'react';
+import { StyleSheet, TextInput, TextInputProps, Text, View } from 'react-native';
+import { COLORS, BORDER_RADIUS, FONT_SIZES } from '@/constants/theme';
+
+interface InputProps extends Omit<TextInputProps, 'style'> {
+  label?: string;
+  error?: string;
+  containerStyle?: object;
+}
+
+export function Input({ label, error, containerStyle, ...props }: InputProps) {
+  return (
+    <View style={[styles.container, containerStyle]}>
+      {label && <Text style={styles.label}>{label}</Text>}
+      <TextInput
+        style={[
+          styles.input,
+          error ? { borderColor: COLORS.danger } : null,
+        ]}
+        placeholderTextColor={COLORS.textMuted}
+        {...props}
+      />
+      {error && <Text style={styles.error}>{error}</Text>}
+    </View>
+  );
+}
+
+const styles = StyleSheet.create({
+  container: {
+    marginBottom: 16,
+  },
+  label: {
+    color: COLORS.textSecondary,
+    fontSize: FONT_SIZES.sm,
+    marginBottom: 6,
+  },
+  input: {
+    backgroundColor: COLORS.backgroundLight,
+    borderColor: COLORS.border,
+    borderWidth: 1,
+    borderRadius: BORDER_RADIUS.md,
+    padding: 12,
+    color: COLORS.text,
+    fontSize: FONT_SIZES.md,
+  },
+  error: {
+    color: COLORS.danger,
+    fontSize: FONT_SIZES.xs,
+    marginTop: 4,
+  },
+});