Address Copilot review: fix serialization and print formatting

Include std_optional_serialization.h for portable std::optional
serialization and fix inconsistent newline in print() labels.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: inuex35

gtsam/navigation/PseudorangeFactor.cpp

@@ -168,7 +168,7 @@ void PseudorangeFactorArm::print(const std::string& s,
   gtsam::print(satClkBias_, "sat clock bias (s): ");
   gtsam::print(Vector(bL_), "lever arm (body frame meters): ");
   if (ecef_T_nav_) {
-    ecef_T_nav_->print("ecef_T_nav:\n");
+    ecef_T_nav_->print("ecef_T_nav: ");
   }
 }
 
@@ -265,7 +265,7 @@ void DifferentialPseudorangeFactorArm::print(
   gtsam::print(satClkBias_, "sat clock bias (s): ");
   gtsam::print(Vector(bL_), "lever arm (body frame meters): ");
   if (ecef_T_nav_) {
-    ecef_T_nav_->print("ecef_T_nav:\n");
+    ecef_T_nav_->print("ecef_T_nav: ");
   }
 }
 

gtsam/navigation/PseudorangeFactor.h

@@ -6,6 +6,7 @@
  **/
 #pragma once
 
+#include <gtsam/base/std_optional_serialization.h>
 #include <gtsam/geometry/Point3.h>
 #include <gtsam/geometry/Pose3.h>
 #include <gtsam/nonlinear/NoiseModelFactorN.h>