Reformat code using clang-format and add CI/CD checks

[supcik]

My goal with this contribution is to simplify the collaboration with contributors. So I added a .clang-format file with settings compatible with the IDF Style Guide. I also added a pre-commit hook to enforce the formatting rules.

Then I added a pre-commit hook to check the code with cppcheck. The tool discovered a couple of issues, so I fixed them.

Finally, I configured the Github actions to check the formatting and to run cppcheck on every commit. I also added a simple example and I use Github actions to compile the example with several architectures (currently esp32 end esp32-s3) and several IDF versions (currently v4.4.7, v5.1.4, and v5.2.1)

Note : This pull request addresses the issue #38.