Ensure LinkScaler validates values

[brooksmtownsend]

At the moment, the LinkScaler only ensures that a link exists between an actor and a provider but does not assert that the values specified are correct. See this TODO for where this code would go: https://github.com/wasmCloud/wadm/blob/main/src/scaler/spreadscaler/link.rs#L119

Essentially we already have this information in the lattice data stream for linkdefs so we should check to see if the linkdef exists so that we can issue a delete and then a put command.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. If this has been closed too eagerly, please feel free to tag a maintainer so we can keep working on the issue. Thank you for contributing to wasmCloud!