Verify the marquee emissive balance and close the facade-realism pass

src/test/tests/test_world.gd

@@ -212,6 +212,27 @@ func test_street_lamps_and_marquee_built() -> bool:
 	root.free()
 	return a and b and TestUtils.check(night_on, "lamps brighten at night") and TestUtils.check(day_off, "lamps dim in daylight")
 
+func test_marquee_emissive_balanced_at_night() -> bool:
+	## The marquee sign face and bulbs are registered with the day/night cycle:
+	## they brighten after dark and fall back to a faint glow in daylight, so the
+	## marquee reads as practical lighting instead of a black box.
+	var root := Node3D.new()
+	var builder := WorldBuilder.new(root)
+	builder.build()
+	var emissive := builder._marquee_emissive
+	var ok := emissive.size() >= 2
+	builder.set_night_mode(true)
+	var night_energy := 0.0
+	for mat in emissive:
+		night_energy += mat.emission_energy_multiplier
+	builder.set_night_mode(false)
+	var day_energy := 0.0
+	for mat in emissive:
+		day_energy += mat.emission_energy_multiplier
+	root.free()
+	return ok and TestUtils.check(night_energy > day_energy,
+		"marquee emissive surfaces brighten at night")
+
 func test_asset_textures_present_and_pow2() -> bool:
 	var required := [
 		"res://assets/textures/brick_facade.png",