Function get_structured_summary 

pub async fn get_structured_summary(
    session_id: String,
    decisions_limit: Option<usize>,
    entities_limit: Option<usize>,
    questions_limit: Option<usize>,
    concepts_limit: Option<usize>,
    min_confidence: Option<f32>,
    compact: Option<bool>,
) -> Result<MCPToolResult, Error>

Generate a structured summary of the session with optional filtering.