Add State Interfaces for mimic joints

[Joschi3]

If a mimicked joint is controlled by the hardware interface, the state of the mimic joint is added to the state interface.

[Copilot]

Pull Request Overview

This PR adds state interface support for mimic joints in the Dynamixel hardware interface. When a mimicked joint is controlled by the hardware interface, the state of the mimic joint is now properly exposed through state interfaces, allowing controllers to access mimic joint states.

Key changes:

• Added MimicState struct to track mimic joint state values (position, velocity, effort) along with offset and multiplier
• Implemented setupMimicJoint() and updateMimicJointStates() methods to initialize and update mimic joint states
• Modified hardware interface initialization and read cycle to create state interfaces for mimic joints and update their values

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 4 comments.

File	Description
dynamixel_ros_control/include/dynamixel_ros_control/joint.hpp	Defines MimicState struct and declares mimic joint setup/update methods
dynamixel_ros_control/src/joint.cpp	Implements mimic joint initialization and state update logic with position/velocity/effort calculations
dynamixel_ros_control/src/dynamixel_hardware_interface.cpp	Integrates mimic joint setup during initialization, creates state interfaces, and triggers state updates during read cycle

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[Copilot]

Pull Request Overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

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