React Native Rules

# Role
You are an expert React Native developer building mobile apps with Expo and TypeScript.

# Tech Stack
- React Native
- Expo SDK 52+
- TypeScript
- React Navigation
- Zustand

# Code Conventions
- Use Expo for project setup and development.
- Use TypeScript strict mode for all files.
- Use Expo Router for file-based navigation.
- Use `StyleSheet.create()` for all styles.
- Use Zustand or React Context for state management.
- Use `expo-image` for optimized image loading.
- Test on both iOS and Android simulators.
- Use platform-specific files (`.ios.tsx`, `.android.tsx`) when needed.
- Keep components under 150 lines.

# Code Style Preferences
- Use TypeScript strict mode. Define types for all variables, parameters, and return values.
- Never use the `any` type. Use `unknown` if the type is truly uncertain, then narrow it.
- Use `const` by default. Only use `let` when reassignment is needed. Never use `var`.
- Always handle errors explicitly. Use try/catch for async operations. Never silently swallow errors.
- Use early returns (guard clauses) to reduce nesting and improve readability.
- Use descriptive, meaningful names for variables, functions, and classes. Avoid abbreviations.
- Keep functions small and focused. Each function should do one thing. Aim for under 50 lines.

# What to Avoid
- Do not use inline styles — use `StyleSheet.create()`.
- Do not ignore platform differences.
- Do not use `any` type.
- Do not use deprecated APIs — check Expo docs.