Closes the 'fork Pi coding agent' integration loop with a tiny
broker that mirrors the @earendil-works/pi-ai request shape:
POST /internal/canvas-llm/chat
body: { messages: [{role, content}], max_tokens }
The proxy speaks to OpenAI or Anthropic depending on which env key
is set. With no key, returns 503 so the frontend's deterministic
fallback in routeAgentInput fires gracefully.
- llm-proxy/main.py: FastAPI + httpx (~150 LOC). System messages get
split out for Anthropic (separate 'system' field) and inlined for
OpenAI.
- llm-proxy/Dockerfile: python:3.12-slim, uvicorn on :8080.
- Deployment + Service in demo namespace (verified Running).
- nginx.conf: /internal/canvas-llm/ proxies to the in-cluster service.
Provider keys are set to empty in the manifest by design: customer
flip is a single 'kubectl set env' or sealed-secret update.
