2007 Prius (!), abs, and vsc codes

My 2007 Prius has the following blink codes:

(!) : 41, 57, 69, 36
abs: 23, 13, 44
vsc: 43, 45

I'm having trouble finding a repair manual, and I figure even if I find all these codes you guys would have a better understanding of what these codes might mean in conjunction.

For context:

2007 Prius w/ 193,000 miles
Been heavily driven for past few months in extremely hot weather, like 110+ degrees

For maybe a month or more, the car would occasionally (maybe 25% of the time) on startup make a very high pitched sound for a few seconds. I believe from other research this indicated the brake accumulator having not enough pressure.

After a few weeks, the (!), abs, and vsc lights would come on at the same time as the sound before quickly going away. All throughout this time, I didn't notice any difference in brake performance or anything.

Yesterday, after starting up the car and driving no more than a mile, the handbrake light came on (handbrake was disengaged), along with the (!), abs, and vsc lights. I still didn't notice any brake performance issues.

I looked up some potential problems and checked those, but those don't seem to be the cause. Brake fluid levels are healthy, inverter coolant fluid levels seem good, and inverter is audibly working. Battery voltage level is perfectly fine at all stages. I plugged in an OBD reader and didn't pick up anything, but I don't think I have the right kind of reader for picking those problems up anyways.

I then got the blink codes above. Also, my TPMS light came on as I was getting the blink codes (morning after), and it was flashing, not solid.

No crash history, and no recent work done on the car.

Any help would be appreciated!