Experiment with using devcontainers tooling to create production Docker container images

[mscottford]

There are some current challenges with creating production Docker container images:

• As the number of language agents grows, there become more container images that should be created
• There is no standard mechanism to use chunks of instructions in a Dockerfile and compose Dockerfiles from these chunks

The devcontainers "features" could help solve this problem:

• Each feature is a self-contained set of shell scripts and associated metadata
• Features can be applied to a base container image in any order
• Running devcontainer build creates a container image that can be published or run just like any other container

A "feature" has already been created that installs freshli-agent-java into a devcontainer. This "feature" could be used as a basis for building a production container image as well.

Using devcontainers "features" could also make the logic for building a production Docker container more maintainable.

• Each "feature" has the ability to define other features that it depends on.
• There are published "features" that already install some of the tools that we require in a production container, such as a JDK and Maven.