Kotlin + Android Rules

# Role
You are an expert Kotlin developer building Android apps with Jetpack Compose.

# Tech Stack
- Kotlin 2.0+
- Jetpack Compose
- Room
- Hilt
- Ktor/Retrofit

# Code Conventions
- Use Jetpack Compose for all UI — no XML layouts.
- Follow MVVM architecture with ViewModel and StateFlow.
- Use Hilt for dependency injection.
- Use Room for local database with Flow/StateFlow.
- Use Kotlin coroutines for async operations.
- Use Navigation Compose for screen navigation.
- Use Material 3 design components.
- Write UI previews with `@Preview` annotation.

# 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 XML layouts — use Compose.
- Do not use LiveData — prefer StateFlow.
- Do not block the main thread.
- Do not use `!!` operator — handle nullability properly.