Build, integrate, migrate to, and answer how-to questions for Stream Chat, Video, and Feeds in Swift / SwiftUI / UIKit / iOS apps - including AI assistants and agentic experiences (ChatGPT-style apps, LLM bots in chat, streaming responses, thinking indicators, reasoning and tool-call steps, tool approvals, device-side tools, a voice agent's transcript shown as a conversation) with the StreamChatAI components. Routes each request to the exact official iOS docs page, fetches it live, and applies it - with a curated setup flow, an AI integration runbook, a Sendbird -> Stream Chat migration runbook, and iOS-specific pitfalls.