Add the optional Forward+ desktop HQ build

Package a Forward+ preset with volumetric fog, SDFGI and a volumetric flashlight
for a separate Linux/Windows Desktop HQ zip. Gate the effects on a real
RenderingDevice, tune LATE fog, and adapt local light falloff for Godot 4.7.
Record the Compatibility/Forward+ A/B captures and metrics, add the artifact to
the build/publish scripts, and keep the default Compatibility/Web path
unchanged. Headless 231/231, Python 87/87; exported HQ binary boots with Vulkan.

src/game/world_builder.gd

@@ -548,7 +548,8 @@ func _build_bulb_canopy() -> void:
 	for x in [-2.2, 2.2]:
 		var omni := OmniLight3D.new()
 		omni.position = Vector3(x, 5.15, front + 1.4)
-		omni.omni_range = 8.0
+		omni.omni_range = 12.0 if Materials.modern_light_falloff() else 8.0
+		omni.omni_attenuation = 0.0 if Materials.modern_light_falloff() else 1.0
 		omni.light_energy = 0.0
 		omni.light_color = Color(1.0, 0.72, 0.36)
 		root.add_child(omni)
@@ -586,7 +587,8 @@ func _add_wall_lantern(pos: Vector3, with_light: bool) -> void:
 		var omni := OmniLight3D.new()
 		omni.name = "LanternGlow"
 		omni.position = pos + Vector3(0.0, -0.1, 0.45)
-		omni.omni_range = 9.0
+		omni.omni_range = 14.0 if Materials.modern_light_falloff() else 9.0
+		omni.omni_attenuation = 0.0 if Materials.modern_light_falloff() else 1.0
 		omni.light_energy = 0.0
 		omni.light_color = Color(1.0, 0.72, 0.38)
 		root.add_child(omni)
@@ -666,7 +668,8 @@ func _build_street_furniture() -> void:
 			holder.name = "Lamp_%d" % int(side)
 			var omni := OmniLight3D.new()
 			omni.position = Vector3(-0.85, 4.65, 0)
-			omni.omni_range = 12.0
+			omni.omni_range = 16.0 if Materials.modern_light_falloff() else 12.0
+			omni.omni_attenuation = 0.0 if Materials.modern_light_falloff() else 1.0
 			omni.light_energy = 0.0
 			omni.light_color = Color(1, 0.93, 0.75)
 			holder.add_child(omni)