Returns aggregated conversation statistics for the specified agent,
including total conversations, qualified leads, qualification rate,
and response rate.
Requires agent_config:view permission.
Bearer token using an API key (format nl_live_* or nl_test_*)
Agent configuration ObjectId
Agent statistics
Total number of conversations using this agent
Number of leads qualified by this agent
Percentage of conversations that resulted in qualification (0-100)
Percentage of conversations where the lead responded (0-100)