Review build failures and signal the reasoning in the Events API

The prod reconciler can't handle build failures. Ideally, we should be able to recover from a build failure if possible.

Otherwise, we should provide more information about the build failure. Is that because we can't find the builder image? Failed to connect to quay?

The more information we get, the better to help users to understand what's wrong. And if possible, try to fire up the build again.

The build failure justification must be signaled to the Events API.