feat(docker): add guided install and saved one-command updates

scripts/docker-update.sh

@@ -69,6 +69,9 @@ if [ "$script_before" != "$(git hash-object scripts/docker-update.sh)" ]; then
   exec 9>&-
   exec bash "$DIR/scripts/docker-update.sh"
 fi
+# Load after pulling so image location changes follow the repository.
+source "$DIR/scripts/docker-config.sh"
+load_docker_config "$DIR" || die "Invalid .docker-install: expected MODE=prebuilt or source and PUBLIC_URL=http(s)://your-host."
 export CMS_RELEASE="$(git rev-parse HEAD)"
 [[ "$CMS_RELEASE" =~ ^[0-9a-f]{40}$ ]] || die "Invalid Git commit."
 [[ -f .env ]] || die "Create .env before installing or updating."
@@ -82,16 +85,16 @@ if [[ -n "$previous_container" ]]; then
   rollback_tag="rollback-$CMS_RELEASE-$$"
   docker image tag "$previous_image" "epicnext-cms:$rollback_tag"
 fi
-log "Building release $CMS_RELEASE from $DIR"
+log "Preparing release $CMS_RELEASE from $DIR"
 # The migrations stage contains matching source and locked dependencies.
 # No Node/package manager installation on the host is required.
 migration_image="epicnext-cms-migrations:$CMS_RELEASE"
 if [[ -n "${CMS_IMAGE_REPOSITORY:-}" ]]; then
   [[ "$CMS_IMAGE_REPOSITORY" =~ ^[a-z0-9.-]+(:[0-9]+)?/[a-z0-9._/-]+$ ]] || die "Invalid CMS_IMAGE_REPOSITORY; use registry/owner/image without a tag."
   log "Pulling prebuilt application and matching migrations for $CMS_RELEASE"
-  docker pull "$CMS_IMAGE_REPOSITORY:$CMS_RELEASE" >>"$LOG_FILE" 2>&1
+  docker pull "$CMS_IMAGE_REPOSITORY:$CMS_RELEASE" >>"$LOG_FILE" 2>&1 || die "Application image unavailable. Publication for this commit may still be running; retry bash cms update after CI succeeds. For private packages, log in to the registry first."
   remote_migration_image="$CMS_IMAGE_REPOSITORY:$CMS_RELEASE-migrations"
-  docker pull "$remote_migration_image" >>"$LOG_FILE" 2>&1
+  docker pull "$remote_migration_image" >>"$LOG_FILE" 2>&1 || die "Matching migrations image unavailable. Current CMS is unchanged; retry after publication succeeds."
   docker tag "$CMS_IMAGE_REPOSITORY:$CMS_RELEASE" "epicnext-cms:$CMS_RELEASE"
   docker tag "$CMS_IMAGE_REPOSITORY:$CMS_RELEASE-migrations" "$migration_image"
 else