Add a validation for backwards compatible agent type evolution

To avoid breaking other components that want to rpc to old versions of an agent, we should only allow changing agent types in a way that agents using the new version of the agent type can still call old versions.
This should be an optional environment level setting.
 See this thread for context: https://zivergeteam.slack.com/archives/C057S2E4XT5/p1765820675009359
