Add support for testing TCP implementations

[Reaves73]

add TCP models and bug patterns

[Reaves73]

I made the first submission according to the professor's suggestions. I know it is not yet fully completed. There might be more revisions later. If there are any deficiencies, please point them out.

[kostis]

As you can see, there are some errors when running the CI tests, although they are quite easy to fix (you can just run spotless:apply and then commit the changed files).

[Reaves73]

Thank you! I’ve corrected the issues, and everything seems to be working now. II wasn’t very familiar with this process before, so I really appreciate your feedback and any further suggestions you might have.

[kostis]

This commit is clearly broken. It should be reverted.

Perhaps it's easier to reset this PR to the commit before it (4fdad8b) and redo whatever changes are necessary after that.

[Reaves73]

yes