* authentication scope, credentials, and authentication scheme.
 *
 * <p>
 * It includes constructors to initialize these details and getter and setter
 * methods to access and modify them.
 * </p>
 *
 * <p>
 * Example usage:
 * </p>
 * <pre>
 * {@code
 * AuthScope authScope = new AuthScope("example.com", 80);
 * Credentials credentials = new UsernamePasswordCredentials("user", "password");

 * methods to add, remove, clear, and retrieve data from these structures.
 *
 * <p>The class is thread-safe due to the use of {@code synchronized} keyword on methods that
 * modify the internal data structures. The internal maps are also declared as {@code volatile}
 * to ensure visibility of changes across threads.
 *

 * The {@link CrawlerContext} class holds the context information for a crawler execution.
 * It contains various attributes related to the crawler's state, configuration, and runtime data.
 * This class provides methods to access and modify these attributes, allowing for control and monitoring
 * of the crawler's behavior.
 *
 * <p>
 * The context includes information such as the session ID, active thread count, access count, crawler status,