Integrate with SpeechRecognition framework on macOS/iOS

macOS and iOS provides two frameworks:

• https://developer.apple.com/documentation/appkit/nsspeechrecognizer?language=objc provides access to the 'command and control' style speech recognition service on the local device
• https://developer.apple.com/documentation/speech/sfspeechrecognizer?language=objc provides access to the cloud-based speech recognition service