v0.1.0

Initial release: portable AgentConfig (schema_version 2) execution on Apple platforms — on-device via Foundation Models (iOS 26 / macOS 26, availability-gated; package floors iOS 17 / macOS 15) and cloud via the Anthropic Messages API behind the same AgentSession protocol. Manifest-driven tools with allow-list semantics, structured output, streaming, turn limits. Includes the FoundationModelsSession field-layout hardening so iOS < 26 class realization cannot fault on weak-linked Foundation Models metadata.