Prevent errors when drawing debug meshes when surface count is zero.

Adds a few checks to ensure a debug collision mesh contains mesh data before
attempting to add it to the gizmo draw list. This prevents errors when using
SeparationRayShape3D, which is only intended to draw a single line, and
contains no mesh data.

Closes #100665

editor/plugins/gizmos/collision_shape_3d_gizmo_plugin.cpp

@@ -350,7 +350,7 @@ void CollisionShape3DGizmoPlugin::redraw(EditorNode3DGizmo *p_gizmo) {
 
 	if (cs->get_debug_fill_enabled()) {
 		Ref<ArrayMesh> array_mesh = s->get_debug_arraymesh_faces(collision_color);
-		if (array_mesh.is_valid()) {
+		if (array_mesh.is_valid() && array_mesh->get_surface_count() > 0) {
 			p_gizmo->add_mesh(array_mesh, material_arraymesh);
 		}
 	}