Fix up the build for `hardhat-ignition-viem`

[kanej]

We want to split the type checks done in the build from the build step, to avoid having to have a contract pre-build step. We want the checks just not in the standard build flow.

When the pre-build step is removed, the packages that depend on hardhat-ignition-viem and currently use it should be updated by removing the script that triggers the pre-build step:

• example-project
• hardhat-toolbox-viem