feat: force-disable the --init flag for linuxserver images

All linuxserver images uses S6, and there are enough of them that this makes sense to autodetect on behalf of users.

plugins/scheduler-docker-local/bin/scheduler-deploy-process

@@ -7,6 +7,7 @@ source "$PLUGIN_AVAILABLE_PATH/checks/functions"
 main() {
   declare APP="$1" IMAGE_SOURCE_TYPE="$2" IMAGE="$3" IMAGE_TAG="$4" PROC_TYPE="$5" PROC_COUNT="$6"
   local CONTAINER_INDEX=1
+  local image_vendor
 
   dokku_log_info1 "Deploying $PROC_TYPE (count=$PROC_COUNT)"
   DOKKU_CHECKS_DISABLED="$(is_app_proctype_checks_disabled "$APP" "$PROC_TYPE")"
@@ -36,6 +37,12 @@ main() {
   done
 
   INJECT_INIT_FLAG="$(fn-plugin-property-get "scheduler-docker-local" "$APP" "init-process" "true")"
+  # special-case linuxserver.io images as those always use an s6-overlay
+  image_vendor="$("$DOCKER_BIN" image inspect --format '{{ index .Config.Labels "org.opencontainers.image.vendor" }}' "$IMAGE")"
+  if [[ "$image_vendor" == "linuxserver.io" ]]; then
+    INJECT_INIT_FLAG="false"
+  fi
+
   PARALLEL_DEPLOY_COUNT="$(plugn trigger "app-json-process-deploy-parallelism" "$APP" "$PROC_TYPE")"
   DOKKU_CHECKS_DISABLED="$DOKKU_CHECKS_DISABLED" parallel --will-cite --halt soon,fail=1 --jobs "$PARALLEL_DEPLOY_COUNT" --ungroup <"$PROCESS_TMP_FILE"