Create VSCode extension to signal whether steps in the DAG are the latest

[pabloarosado]

It would be useful to see in the DAG whether a certain step (and their dependencies) is the latest version.

This could possibly be achieved with a VSCode extension. It would run in the background and:

• Read the content of all yaml files in the dag folder (skipping the archive).
• List all unique steps.
• Find the latest version of each step.
• Add a message, e.g. "⚠ There's a newer version, 2025-03-01", or "✅ Latest version" next to each step in the dag (similar to what GitLens shows). Alternatively, it could show that on hover over the step.

I'm not sure how hard it would be to achieve this, but we could try it during a cooldown.

[pabloarosado]

Another related idea would be to speed up find_latest_etl_step by letting it read the dag, instead of scanning all files.