Refactor the URDF into multiple parts.

Makes it easier to work on an individual part in isolation.
Also change the vscode devconsole visualiser to one that works with includes

robot/src/raspbot_v2/urdf/camera.xacro

@@ -0,0 +1,83 @@
+<?xml version="1.0"?>
+<robot xmlns:xacro="http://www.ros.org/wiki/xacro">
+
+  <!-- ─────────────────────────────────────────────────────────────────────
+       Camera module
+
+       Mounted on camera_tilt_link (output of the tilt joint in pan_tilt.xacro).
+
+       Two frames are defined:
+         camera_link         — physical body of the camera module
+         camera_optical_frame — REP-103 optical frame (Z forward, X right, Y down)
+                                used as the sensor origin in Gazebo and ROS image topics
+       ───────────────────────────────────────────────────────────────────── -->
+
+  <!-- Physical camera body — visual only, small box representing the module -->
+  <link name="camera_link">
+    <visual>
+      <geometry><box size="0.025 0.06 0.02"/></geometry>
+      <material name="blue"/>
+    </visual>
+    <collision>
+      <geometry><box size="0.025 0.06 0.02"/></geometry>
+    </collision>
+    <inertial>
+      <mass value="0.03"/>
+      <inertia ixx="0.000005" ixy="0" ixz="0"
+               iyy="0.000005" iyz="0" izz="0.000005"/>
+    </inertial>
+  </link>
+
+  <joint name="camera_joint" type="fixed">
+    <parent link="camera_tilt_link"/>
+    <child  link="camera_link"/>
+    <origin xyz="0.01 0 0" rpy="0 0 0"/>
+  </joint>
+
+  <!-- REP-103 optical frame: Z forward, X right, Y down.
+       The rpy="-pi/2 0 -pi/2" rotation maps the body frame (X-fwd, Y-left, Z-up)
+       to the optical frame convention expected by image_geometry and cv_bridge. -->
+  <link name="camera_optical_frame"/>
+
+  <joint name="camera_optical_joint" type="fixed">
+    <parent link="camera_link"/>
+    <child  link="camera_optical_frame"/>
+    <origin xyz="0 0 0" rpy="${-pi/2} 0 ${-pi/2}"/>
+  </joint>
+
+  <!-- ─────────────────────────────────────────────────────────────────────
+       Gazebo camera sensor  (Gazebo Harmonic / gz-sim)
+
+       Image data is published on gz topics and bridged to ROS 2 via
+       ros_gz_bridge:
+         /camera/image  (gz) → /camera/image_raw  (ROS 2)
+         /camera/info   (gz) → /camera/camera_info (ROS 2)
+       ───────────────────────────────────────────────────────────────────── -->
+  <gazebo reference="camera_link">
+    <sensor name="camera" type="camera">
+      <always_on>1</always_on>
+      <update_rate>30</update_rate>
+      <visualize>true</visualize>
+      <camera>
+        <horizontal_fov>${camera_fov}</horizontal_fov>
+        <image>
+          <width>${camera_width}</width>
+          <height>${camera_height}</height>
+          <format>R8G8B8</format>
+        </image>
+        <clip>
+          <near>0.05</near>
+          <far>50.0</far>
+        </clip>
+        <noise>
+          <type>gaussian</type>
+          <mean>0.0</mean>
+          <stddev>0.007</stddev>
+        </noise>
+      </camera>
+      <!-- Publishes to gz topic /camera/image -->
+      <topic>/camera/image</topic>
+    </sensor>
+  </gazebo>
+
+</robot>