[messaging] Enhance Expo notification icon configuration support and documentation#8618

Copilot wants to merge 4 commits intomaininvertase/react-native-firebase:mainfrom

copilot/fix-afbd3d5c-4c1c-4216-87b6-5ec1ba94028dinvertase/react-native-firebase:copilot/fix-afbd3d5c-4c1c-4216-87b6-5ec1ba94028dCopy head branch name to clipboard