As we're already introducing an MCU nearby the stepper motors, it wouldn't be too difficult to implement a current monitoring circuit that could be tuned to detect stalls and jams.
The circuit would simply need a small-value resistor, or even a serpentine trace with a known resistance, and two ADC pins, or a differential amp circuit and one ADC pin, to detect current spikes, which could then be relayed to the main MCU over I2C
As we're already introducing an MCU nearby the stepper motors, it wouldn't be too difficult to implement a current monitoring circuit that could be tuned to detect stalls and jams.
The circuit would simply need a small-value resistor, or even a serpentine trace with a known resistance, and two ADC pins, or a differential amp circuit and one ADC pin, to detect current spikes, which could then be relayed to the main MCU over I2C