Adds a method for printing active release trains for a configured
project. This is helpful for the release tool that will print
the active release trains. Also this can be useful for the
caretaker status command, where we could print the active
version branches (i.e. "is there currently a feature-freeze branch").
PR Close#38656
Adds logic for determining active LTS branches for a given
release configuration. The active LTS branches can be determined
by querying NPM and matching dist tags against a specific
pattern. i.e. `v{major}-lts`.
This logic will be useful for the release tool that supports
publishing of active LTS version branches.
PR Close#38656
We initially added logic for determining active release trains into
the merge script. Given we now build more tools that rely on this
information, we move the logic into a more general "versioning" folder
that can contain common logic following the versioning document for the
Angular organization.
PR Close#38656
Paul Gschwendtner