The Observable OccViewer.Observable and IPromise OccViewer.IPromise constructs provide mechanisms for handling asynchronous operations and event-driven workflows within LWV, allowing JavaScript and C++ codebases to interact seamlessly. These utilities ensure efficient memory management, callback registration, and error handling. The Observable represents class which allows to add many callbacks in subscribe function and call emit to fire all subscribed callbacks. The IPromise interface bridges JavaScript promises with asynchronous C++ operations, ensuring proper callback execution and error handling.