Introduce Factory design mode for ros2_openvino_toolkit

The current programming modeling in the project is not friendly to add new extensions (e.g. adding new types of for Data Input, AI Model or Result Output).

We had been doing some attempts by adopting Factory design patterns in another repo ( [PR ](https://github.com/intel/ros_openvino_toolkit/pull/194) support for [ros_openvino_toolkit](https://github.com/intel/ros_openvino_toolkit)). And as a result of evaluation, we think the method is more friendly to new contributers and reducing the repeated code in the whole project.

So we want the tasks to be done such as:
- Migrating the draft implementation into the repo(ROS2_OpenVINO_toolkit).
- [Optional] Evaluate the impacts to the current functions (comparing with the functions once Factory mode adopted), document them or find the resolution.