Fix docker caching and correcting version in Gitea workflow

docker/entrypoint.sh

@@ -0,0 +1,17 @@
+#!/usr/bin/env bash
+# Runtime entrypoint: pulls the latest .deb artifact from Gitea Actions and
+# installs it on every container start, then execs the CMD (hbbs / hbbr).
+#
+# Configuration comes from the environment — see docker-compose.yml:
+#   ARTIFACT_URL    pinned zip URL; if unset the script discovers the newest
+#                   successful run on GITEA_BRANCH
+#   GITEA_URL, GITEA_OWNER, GITEA_REPO, GITEA_BRANCH
+#                   required when ARTIFACT_URL is unset
+#
+# Container fails to start if the fetch fails — that's intentional: we always
+# want a fresh artifact, never a stale one.
+set -euo pipefail
+
+/usr/local/sbin/fetch-artifact.sh
+
+exec "$@"