Actually according to the documentation both direction and compassDirection should refer to the direction the wind is coming from. Respectively,
Direction the wind is coming from in degrees, with true north at 0 and progressing clockwise from north.
...and:
General indicator of wind direction, often referred to as “due north”, “due south”, etc. Refers to the direction the wind is coming from, for instance, a north wind blows from north to south.
In the example Wind object:
WeatherKit.Wind(compassDirection: East, direction: 90.0 °, speed: 7.09 km/h, gust: Optional(18.18 km/h))
It’s indicating “wind out of the east” (as a simplified weather report may phrase it), specifically from compass direction 90º, which is due east.
A wind blowing from due west would be blowing from a direction of 270º.