The k8s manifest was missing the Box runtime that backs the sandbox
tools, the activate skill tool, skill add/edit and stdio MCP. Add a
langbot-box Deployment/Service (port 5410), wire langbot to it via
BOX__RUNTIME__ENDPOINT (explicit Service name since the in-container
default langbot_box uses an underscore, invalid for k8s DNS), and share
the Box workspace root as a node hostPath pinned via podAffinity so the
node Docker daemon resolves bind-mount paths consistently. Document the
component, the shared-FS constraint, security implications and readiness
checks in README_K8S.md (zh + en).
All documentation URLs now go through Cloudflare Bulk Redirects
(link.langbot.app) so future doc path changes won't break
already-released versions.
Short link format: link.langbot.app/{lang}/docs/{topic}
Supported languages: zh, en, ja
