* cannon: Support F_GETFD cmd to fcntl.

* cannon: Update fuzz test expectations.

* cannon: Update MIPS.t.sol

* cannon: Introduce a new state version for supporting get_fd.

Switches singlethreaded prestate to use .bin.gz instead of json since it now needs to detect the new state version.

* cannon: Don't override the cannon version.

* Update semver-lock.

* cannon: Update tests to detect old versions but only check writing and parsing for the currently supported versions.

* cannon: Load old version from cannon docker image

* cannon: Improve logging.

* cannon: Restore cannon version arg.

* Fix contrac semvers.

* cannon: Rename singlethreaded-getfd to just singlethreaded-2.

We could just go to using the state version number directly, but particularly the difference between singlethreaded and multithreaded feels useful to keep.

* cannon: Fix comment.

* Update semver again.