* feat: Use encodeCall for type safety

A very common issue (both from experience and observation) is
failing to correctly encode the initializer arguments in
`encodeSystemConfigInitializer()`. This fixes that.

I believe that at one point we needed to be able to pass the 4 bytes
selector in as a string, but that no longer seems to be the case.

* semver

* feat: expand use of encodeCall to rest of OPCM

* semver lock