cloud SDK, how to get a publisher working locally with an author instance?

running a publisher and author instance is easy:

cd /author

java -jar aem-author-p4502.jar

cd /publish

java -jar aem-publish-p4503.jar

We can then login to author (http://localhost:4502):, see all our sites pages, and even publish them all.

However, on our local publish instance, there is nothing. no content.  e.g. if we navigate to:  http://localhost:4503/content/ourweb-web/oursite_com/uk/en/legal.html we get 404

We get that path by editing the page in the author instance, then copying the path.

Presumably we have to manually configure replication agents on author/publish. I got this working long ago, but it stopped working soon after, and I dont know how to debug it.

how does one setup a local publish instance to work with a local author instance?

If I look on publish instance CRX editor thing, I dont see our sites under "conent":

http://localhost:4503/crx/de/index.jsp

Note: i installed our app on the author instance using:

mvn clean install -PautoInstallPackage

I installed our content on the author instance using a package.

I just found this documentation page on how to setup replication agents: https://experienceleague.adobe.com/docs/experience-manager-learn/cloud-service/local-development-environment-set-up/aem-runtime.html?lang=en#content-distribution

Now I just get blank pages instead of 404.

I know I need to find a way to replicate the content, how do I replicate the code?