Function create_deep_agent

pub fn create_deep_agent(
    params: CreateDeepAgentParams,
) -> Result<DeepAgent, Error>

Create a deep agent - matches Python create_deep_agent() API exactly

This is the main entry point that mirrors the Python SDK:

agent = create_deep_agent(
    tools=[internet_search],
    instructions="You are an expert researcher...",
    model=model,
    subagents=subagents,
    checkpointer=checkpointer,
    tool_configs=tool_configs
)