Agora RTC Objective-C API Reference Refactor

### - h -

- height : AgoraEncodedVideoFrameInfo , AgoraExtVideoFrame , AgoraFacePositionInfo , AgoraOutputVideoFrame , AgoraRtcRemoteVideoStats , AgoraVideoFilterFrame , AgoraVideoFrame
- highLightColor : AgoraScreenCaptureParameters
- highLighted : AgoraScreenCaptureParameters
- highLightWidth : AgoraScreenCaptureParameters
- hwDecodingLevel : AgoraVideoCodecCapLevels