feat(api-caller): Hard-disable all IRQs during API calls
Disable all maskable interrupts on core 1 during API calls. This brings two main advantages: 1. It means API calls are now always ISR-safe and can be used everywhere in core 1 code. This is mostly interesting to l0dables as Pycardium should not need to do this. 2. It allows Epicardium to halt the clock for core 1 without fear as we have observed problems with doing this when core 1 is currently executing instructions that touch memory. Now a synchronous call from core 1 will guarantee that it is currently waiting in a WFE and no other ISRs could be potentially running.