feat: add release-to-move TCP gizmo control in Webots

Add a native Webots marker for setting the active tool's TCP position and
orientation. Dragging edits the preview; releasing the mouse submits one
complete, checked joint trajectory with configured TCP speed limits.
Unreachable targets reset the marker to the current TCP.

Preserve coordinate, joint, and control-file commands through motion
reservations and a controller action proxy. Give the gizmo lowest priority
and finish its committed trajectory before dispatching queued regular
commands, including waits longer than the former two-second service timeout.

Place the patron TCP at its working end, 55.2 mm along local Z, and use the
flange TCP when no tool is attached. Add digital_twin.tcp_gizmo configuration,
ROS interfaces, launch integration, and regression coverage.

Document operation, configuration, tool attachment, speed limits, and
troubleshooting in both Russian and English.

Validation: 42 Python tests and 8 C++ tests passed. Webots regressions covered
one action per release, translation and rotation with and without a tool,
unreachable targets, and ordinary commands waiting for gizmo completion.

src/iiwa_description/urdf/tools/patron.xacro

@@ -107,7 +107,8 @@
     </joint>
 
     <joint name="patron_tcp" type="fixed">
-        <origin xyz="0.0 0.0 0.0" rpy="0.0 0.0 -1.5708"/>
+        <!-- Working end of patron.dae, 55.2 mm from the patron link origin. -->
+        <origin xyz="0.0 0.0 0.0552" rpy="0.0 0.0 -1.5708"/>
         <parent link="patron"/>
         <child link="tcp"/>
     </joint>
@@ -174,4 +175,4 @@
         </sensor>
     </gazebo> 
 
-</robot>
+</robot>