I would bet that any non-zero solar production at night is a measurement error. Mine shows 1W generated all night. My inverter actually turns off at night, and I believe that includes a relay physically disconnecting it. It turns on once a sufficient voltage is reached (I think ~150-200V in my system), and off once it goes below the threshold voltage for several minutes continuously. That means that it actually is a power draw for about 10 minutes in the morning (10W to 0) and 30 minutes at night (0 to 20W).
Fireworks, the moon, and streetlights aren’t sufficiently bright to get enough voltage to turn the inverter back on, so they generate nothing. Potentially, you could measure some power directly off the panel with sensitive enough equipment, but it would never exceed the losses of an inverter.