描述
Implement, fix, debug, review, or refactor Flutter networking code for HTTP/REST APIs, WebSocket realtime flows, authentication and token refresh, request headers, timeouts, retries, JSON parsing, caching, background isolates, repositories, services, and adaptation to existing http, Dio, Retrofit, Chopper, or custom API clients. Use when asked to add network requests, investigate network errors, harden API clients, handle auth, or validate Flutter network behavior.