feat: add multi-stage Dockerfile with claude CLI runtime

Dockerfile

@@ -0,0 +1,45 @@
+# syntax=docker/dockerfile:1
+
+# ── Build stage ───────────────────────────────────────────────────────────────
+FROM golang:1.26-bookworm AS builder
+
+ARG VERSION=dev
+WORKDIR /src
+
+COPY go.mod go.sum ./
+RUN go mod download
+
+COPY . .
+RUN CGO_ENABLED=0 GOOS=linux GOARCH=amd64 \
+    go build -trimpath -ldflags="-s -w -X main.version=${VERSION}" \
+    -o /out/supervisor ./cmd/supervisor
+
+# ── Runtime stage ─────────────────────────────────────────────────────────────
+# Node.js 22 slim — needed for claude CLI subprocess
+FROM node:22-slim
+
+# Install claude CLI (provides the `claude` binary the supervisor shells out to)
+RUN npm install -g @anthropic-ai/claude-code \
+    && claude --version \
+    && echo "claude CLI installed"
+
+# Copy supervisor binary
+COPY --from=builder /out/supervisor /usr/local/bin/supervisor
+
+# Bake in config (models.yaml + skill discipline files)
+COPY config/ /app/config/
+
+WORKDIR /app
+
+# brain/ is writable state — mount a PersistentVolume here
+VOLUME /app/brain
+
+ENV SUPERVISOR_CONFIG_DIR=/app/config/supervisor
+ENV SUPERVISOR_MODELS_FILE=/app/config/models.yaml
+ENV SUPERVISOR_BRAIN_DIR=/app/brain
+ENV SUPERVISOR_SESSIONS_DIR=/app/brain/sessions
+ENV SUPERVISOR_PORT=3200
+
+EXPOSE 3200
+
+ENTRYPOINT ["/usr/local/bin/supervisor"]