Adjust IMU pitch offset from -6° to -8°

Fine-tuned based on live testing — robot still leaned slightly back at -6°.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

gear_sonic_deploy/src/g1/g1_deploy_onnx_ref/include/input_interface/gamepad_manager.hpp

@@ -48,7 +48,7 @@
 
 /// Runtime-adjustable IMU pitch offset (degrees). Keys 9/0 to adjust.
 /// Accessed from G1Deploy::UpdateRobotState() to correct base_quat.
-inline std::atomic<double> g_imu_pitch_offset_deg{-6.0};
+inline std::atomic<double> g_imu_pitch_offset_deg{-8.0};
 
 #if HAS_ROS2
 #include "ros2_input_handler.hpp"