feat: Claude Code Monitor — lanes, pipelines and a merged workspace

Internal SmartGift build of a Claude Code monitoring dashboard.

Lanes: a durable unit of parallel agent work, one per working directory,
tracked across session restarts. Managed lanes are git worktrees the
dashboard provisions and can reset or remove behind a three-check destroy
guard and a counted preflight; adopted lanes are directories you already
own and are never destroyable.

Pipelines: a lane moves through pipeline stages. A stage the agent declares
with evidence renders green; a stage inferred from the tool-event stream
renders dashed amber and never counts as done. Detection is forward-only
within a 30-minute window, and never writes the declared stage.

Workspace: one page at /run with a lane grid, the selected lane's pipeline,
and a full Claude console behind a disclosure.

mcp/Dockerfile

@@ -0,0 +1,35 @@
+# syntax=docker/dockerfile:1.7
+
+# Build context must be the repository root so the local file dependency
+# ("agent-dashboard": "file:..") resolves correctly.
+
+FROM node:22-alpine AS deps
+WORKDIR /workspace
+
+COPY package.json package-lock.json ./
+COPY mcp/package.json mcp/package-lock.json ./mcp/
+
+RUN npm --prefix mcp ci --omit=dev
+
+FROM node:22-alpine AS build
+WORKDIR /workspace
+
+COPY package.json package-lock.json ./
+COPY mcp/package.json mcp/package-lock.json ./mcp/
+
+RUN npm --prefix mcp ci
+
+COPY mcp ./mcp
+
+RUN npm --prefix mcp run build
+
+FROM node:22-alpine AS runtime
+WORKDIR /app
+
+ENV NODE_ENV=production
+
+COPY --from=deps /workspace/mcp/node_modules ./node_modules
+COPY --from=build /workspace/mcp/build ./build
+COPY --from=build /workspace/mcp/package.json ./package.json
+
+ENTRYPOINT ["node", "build/index.js"]