TanStack AI 1.0 stabilizes its core; the agent harness remains experimental

TanStack AI 1.0 stabilizes its core APIs for combining chat, tools, media, and integrations across multiple providers and UI frameworks. Tree-shakable adapters and end-to-end tests using deterministic fixtures check the flows without live model calls.

The agent harness adds durable sessions, interrupts, and background work, but remains 0.x and may change in minor releases. Upgrading requires moving the stable packages together and supplying a threadId explicitly; passing the type check does not migrate persisted conversations or files.