100d-auto-night-light shipped `dark: "1M"` meaning 1 megaohm. The value
parser follows the SPICE convention where M is MILLI and mega is `Meg`,
so the dark resistance became 0.001 ohm. With the divider's top leg a
short, AO sat at VCC: `ldr.read()` returned 4095 on every sample, the
sketch's `light < 500` branch never ran, and the lamp LED never lit.
Dragging the lux control changed nothing either, because every lux value
still divides a short (measured n1 = 3.299999996 V, which is exactly what
100k / (100k + 0.00011) predicts).
The netlist snapshot had frozen the bug in place:
- R_night-ldr_ldr vcc_rail n1 0.00011111111111111112
+ R_night-ldr_ldr vcc_rail n1 111111.11111111111
Diagram now says "1Meg" (regenerated from test/test_100_days), and the
mapper clamps a sub-1k dark resistance to the documented 1Meg default
with a console warning naming the milli/mega trap — a photoresistor that
reads as a short is always this mistake, and it fails in the most
confusing way possible: the part looks alive, it just never moves.