RestApiClientImpl class

Implementation of the RestApiClient interface using the Dio HTTP client.

This class provides a complete REST API client with support for:

• All standard HTTP methods (GET, POST, PUT, PATCH, DELETE, HEAD)
• JWT authentication with automatic token refresh
• Response caching with configurable lifetime
• Request retry with exponential backoff
• Request deduplication for concurrent identical requests
• File downloads with progress tracking

Example usage:

final client = RestApiClientImpl(
  options: RestApiClientOptions(baseUrl: 'https://api.example.com'),
  authOptions: AuthOptions(
    refreshTokenEndpoint: '/auth/refresh',
    resolveJwt: (response) => response.data['access_token'],
    resolveRefreshToken: (response) => response.data['refresh_token'],
  ),
);

await client.init();

final result = await client.get<User>(
  '/users/me',
  onSuccess: (data) => User.fromJson(data),
);

if (result.hasData) {
  print(result.data!.name);
}