Ooooohhh, this isn't something I have done first hand, sort of, but this is something I have always thought about.
Some years ago I bought a greenhouse kit. Aluminum frame with corrugated panels, 10x12 (i think). So, the next year I bought my largest amount of peeps (48) and I set them up on one side of the greenhouse. My thought was that I would raise them in the greenhouse, separate from the other
chickens and then transfer them to a new coop with all the others. Well, they ended up living a whole year, even a winter in the greenhouse, and we ended up moving, so they came to the new house and a new coop.
But, I did keep good track of the temperature inside the greenhouse while they were living there and even when the winter winds were blowing the inside temp never fell below freezing, in fact the coldest was in the upper 30's to 40's. Without the chickens the greenhouse would be a few degrees different then the outside temps, but once the outside temp fell below 20 the greenhouse was the same inside and out.
So, I came up with this great idea. Put a hoophouse type greenhouse into the garden, at least 6-feet high so walking inside isn't a problem. Then wire off a section on one end and put in chickens through the winter, probably some boys from the last years hatch or even some late in the summer rooster orders from a hatchery. Then you have chicken to eat through the winter, with most of them being harvested in the spring when the weather improves AND the presence of the chickens keeps the temperature of the greenhouse able to grow cold crops through the winter.
Needless to say this never happened, but I did learn that it would be possible with a hearty winter breed in my climate (western pa) based on my flock in a greenhouse kit. My girls stick close to home in the winter, so I wouldn't do this in the summer heat, but for winter it would work because the chickens are less likely to mind being cooped up in the bad weather and their presence helps with the temperature in the cold.
Since quail are much smaller, I would think it would work, but you may need more birds.
Tami