Space,
lots of space, is your biggest ally in winter chickeneering.
Diversions are great, but nothing makes up for lack of space, IMO.
My run is not sheltered but for a small 4x8 area under the coop,
so my coop is big, or rather I keep the population down for wintering over.
We gets
lots of snow here, I shovel out part of the run and a path for me to keep mesh roof cleared, allow some more space for birds, and to speed ground clearing at snow melt season. I toss scratch grins out in the mornings to get them outside. They don't like the snow much but get used to it, some more than others. I'll toss out a thin layer of straw if it gets icy.
I keep feed and water inside coop, easier for me to tend to it and I use lights so they need to eat before pop door gets opened at day break.
There lots of ways to keep water thawed,
this is what I use.