Function query 

pub async fn query(
    __arg0: State<Arc<AppState>>,
    __arg1: Json<QueryRequest>,
) -> impl IntoResponse

Execute a VelesQL query.

BUG-1 FIX: Automatically detects aggregation queries (GROUP BY, COUNT, SUM, etc.) and routes them to execute_aggregate for proper handling.

DDL statements (CREATE/DROP COLLECTION) are intercepted before collection resolution and dispatched directly through Database::execute_query.