Update all example projects to use the new Compose integration

[kiview]

All examples should use the new first-class Compose integration with Docker Model, as documented in https://docs.docker.com/ai/compose/models-and-compose/.

In addition, a GHA workflow should be added, that performs a very simple smoke test against each project, spinning it up using Docker Compose.

The GHA should ensure Docker Model Runner is installed, following these instructions:
https://docs.docker.com/ai/model-runner/#enable-dmr-in-docker-engine