The v1.4.42 docker-publish workflow shipped a stale package.json version
baked into the bundle because BuildKit reused the pnpm build layer
across the release tag bump -- the COPY . . layer key was content-stable
relative to the prior build, the layer was warm, and the runtime
/api/version read the cached package.json content instead of the new
tag.
Thread github.ref_name through as a NEXT_PUBLIC_APP_VERSION build-arg
from docker-publish.yml. The Dockerfile picks it up as an ARG/ENV in
both the builder and runner stages and bakes it into the build context.
src/app/api/version/route.ts now reads the env var first and falls
through to package.json only when unset (local pnpm dev). The build-arg
becomes part of the layer cache key, so every release tag invalidates
every downstream layer and the runtime version can never drift from
the tag the workflow ran on.