Ergonomic top-level Agent SDK facade for the Bamboo agent framework.
This crate is the thin, ergonomic entry point over the engine runtime. It
depends only on the lower layers (bamboo-engine, bamboo-infrastructure,
bamboo-tools, bamboo-agent-core, bamboo-domain) and never on
bamboo-server, so it can be reused freely by server/engine code without a
circular dependency.
See [agent] for the full surface; the most common entry points are
[Agent] and [AgentBuilder].