I know you're talking to the Pacific Northwest, people because it got a little warm up there last week. However, those of us that live in the Southern Pacific are better suited to answer questions about heat because we get 110f+ for several months on end. Last month it was usually over 100f by 9am where I live in the Mojave desert, and that trend will usually continue till about late August.
The car does just fine in the heat, just gotta make sure cabin overheat protection is on to keep the cabin below 105f. It does eat some battery having to turn on all the time but depending on the parking situation it can vary on how often it has to turn on. My old job i had to park in the open sun and there was no shade to park under the AC was turning on and off constantly almost because the sun was just beating down on the car. But now my office has covered areas and i make sure to park in the area that will have shade for the longest period of time. It still turns on all the time but not nearly as often as it did in my last office. I also have ceramic 30% tint on all the glass except the front windshield because i had a crack at the time and they don't tint if you have a crack. So that definitely helps block some heat as well.
When driving and its 118f outside and the car Ac is set to 69f it works just fine. of course having it set like 40f lower than the outside temp does mean it will stay on running hard which eats power but whatever it works great.
For your supercharging question, its the same it works fine. However, I do not recommend sitting in the car for the first 10-15 min of supercharging when its hot AF outside because the car will divert cooling power from the cabin to the battery so it gets toasty in the cabin for the first bit of the stop. But then once the SC speed drops and the AC can keep up with cooling the battery and the cabin you're fine to hang out in there till it is done charging.
I have the original AC unit in my 2014 with 119k miles and I've lived in the desert for almost 3 years now.
On a side note, IMO the car uses less juice to keep the cabin/battery cool on hot days than it does warming the battery on cold drives. I have no actual evidence of this, its purely anecdotal based on my living in the desert and vacationing in the mountains during winter.