[DOCS] Add Code of Conduct

[SeungjaeLim]

Description

The project requires a CODE_OF_CONDUCT.md file to establish a set of community guidelines and expectations for contributors and maintainers, promoting a welcoming and inclusive environment.

Location

homey/CODE_OF_CONDUCT.md

Proposed Changes

1. Create a CODE_OF_CONDUCT.md file in the root directory of the project.
2. Use a standard template, such as the Contributor Covenant, as a starting point for the code of conduct.
3. Customize the template as needed to fit the project's values and expectations.
4. Include information on how to report violations of the code of conduct and the process for handling these reports.

Additional Context

A CODE_OF_CONDUCT.md file helps to create a positive and inclusive atmosphere within the project's community. It sets expectations for behavior and provides a framework for addressing and resolving conflicts and issues that may arise.