Move tools.go to its own module

[lcarva]

As mentioned in the docs for tools.go, the dependencies used there are only meant to be used in scripts. Let's isolate those dependencies in their own go module to formalize their usage.

We could turn the parent directoy, hack, into a go module, for example. This would likely require changes in other scripts and maybe CI.

The main benefit of this approach is that CVEs found in those dependencies do not impact the Chains controller.