Whenever an invariant fails, Medusa should create a foundry test

[bsamuels453]

We would be incorporating fuzz-utils into medusa.

Whenever an invariant fails, Medusa would create a foundry test to reproduce the failure. The user would be notified of the test's existence after the sequence is fully shrunk, and once again at the end of the medusa run:

A foundry test was created to reproduce this failure. Run foundry test ./medusa/tests/3423423432342.sol -vvv to debug