Implement a lodging reservation widget with: ( 1) inputs for check-in and check-out dates; compute total price based on nightly rate, length of stay, and dynamic pricing that changes with selected adults and children; ( 2) validation that check-out is after check-in and that guest counts do not exceed capacity; ( 3) a disabled “Book Now” button when the room is sold out or selection is invalid; ( 4) a confirmation dialog on submit. Describe component state, data models, and error states; outline how you would test edge cases such as minimum nights, partial availability, timezone/daylight-saving transitions, and price rounding.