Place U1, C1, C2, C3, R1, R2 in the left open area (x=73-86, y=48-60)
of the board outline. Add copper traces for +12V bus (U1 input to
existing +12V net via A4988), +5V bus (U1 output to ESP32 VIN and C2),
and limit switch signals (/LIM_A to SW1, /LIM_C to existing trace).
Remove orphaned net-0 segments and clear zone fills for regeneration.