What is the problem you're trying to solve

The event system in Containerd is helpful to react on content changes without having to periodically poll for changes. The events that exist today cover things like images, content, and containers. The image events cover create, update, and delete events.

https://github.com/containerd/containerd/blob/main/api/events/image.pb.go

There is some discrepancy with the content events which only cover delete events.

Describe the solution you'd like

I would like to introduce a new event called ContentCreate alongside the existing event ContentDelete.

https://github.com/containerd/containerd/blob/c3bed76eeb24ab6671a8134ce32fd2b22b0af667/api/events/content.pb.go#L39C6-L45

I do not think an update event would be too interesting as the content cant really change without changing the digest. Adding a create event would bring the events up to par with the other event types.

Additional context

No response