Represents a source (app or device) that has contributed health data to HealthKit.
Obtained via AFHealthTracking.fetchStepDataSources() (iOS / watchOS only).
AFHealthTracking.fetchStepDataSources()
Bundle identifier of the source app, if available (e.g. "com.apple.health.DF29582A-26BA-…").
Display name of the source (e.g. "iPhone", "Apple Watch", "Strava").