screen-orientation

c1b94559 - Refactor fullscreen rejection handling to use WebIDL react pattern

Refactor fullscreen rejection handling to use WebIDL react pattern This commit modernizes how the Screen Orientation specification responds to fullscreen request rejections by using the WebIDL 'react' concept instead of the previous flag-based approach. Changes: - Replace flag-based 'pending fullscreen request flag unset due to rejection' pattern - Use WebIDL 'react' pattern with 'pending fullscreen request promise' - Update reference to use proper 'pending fullscreen request flag' terminology - Extract duplicated descendant document logic into helper algorithm 'reject descendant document orientation promises' - Remove redundant fullscreen exit handling (already handled by Fullscreen spec) - Add clarifying notes for algorithm logic and same-origin security restrictions - Maintain all existing algorithm behavior while modernizing the specification architecture This enables cleaner, more maintainable specification text that follows modern WebIDL patterns for promise-based APIs and eliminates code duplication. The change complements the fullscreen spec changes in whatwg/fullscreen that add both the exported flag and promise definitions needed for this integration. Fixes #254 Fixes #255