fix(images): 服务器镜像在创建时固定到仓库 digest，更换镜像需确认备份，安装器重建前先固定旧服并推送不可变版本标签

panel/src/i18n/resources/en-US/errors.json

@@ -7,6 +7,9 @@
   "quota_exceeded": "You have reached your server quota.",
   "already_claimed": "Someone else just claimed this server.",
   "image_not_whitelisted": "That image is not on the whitelist.",
+  "image_not_in_registry": "The internal registry doesn't hold that image tag — it was never pushed or has been deleted. Rebuild or push it, then try again.",
+  "registry_unavailable": "Can't reach the internal registry to look up which build that image is — try again shortly.",
+  "image_change_unconfirmed": "Changing the image opens the world with the new build's Minecraft version, and upgraded chunks can't be opened by the old one again. Back the world up, tick the confirmation, then save.",
   "subdomain_taken": "That subdomain is already in use.",
   "already_exists": "A server with that name already exists.",
   "cooldown": "Wake is cooling down — try again shortly.",