[Health] Expand writeWorkoutData with metadata parameter e.g. label workout as indoor

[basvdijk]

Description

Expand writeWorkoutData with the option to add metadata. Especially the indoor key. I am building a rowing trainer app and I can only add the rowing activity. There is no way to set theindoor flag.

Additional information

• https://developer.apple.com/documentation/healthkit/hkmetadatakeyindoorworkout?language=objc
• https://stackoverflow.com/questions/56534009/how-i-define-my-activity-as-indoor-cycling-using-cychealthkithandler