Restore the from-source Dockerfile for Railway branch builds

Dockerfile

@@ -0,0 +1,39 @@
+# syntax=docker/dockerfile:1
+FROM node:24.18.1-bookworm-slim AS node
+
+FROM rust:1.97.1-bookworm AS sdk
+COPY --from=node /usr/local/bin/node /usr/local/bin/node
+WORKDIR /app
+# Dashboard edits must not invalidate this layer.
+COPY core/ core/
+# Railway requires its literal service ID; BuildKit on Ployz accepts the same cache IDs.
+RUN --mount=type=cache,id=s/8089d161-49d3-4c77-b683-2bede5a784f5-/usr/local/cargo/registry,target=/usr/local/cargo/registry \
+    --mount=type=cache,id=s/8089d161-49d3-4c77-b683-2bede5a784f5-/usr/local/cargo/git,target=/usr/local/cargo/git \
+    --mount=type=cache,id=s/8089d161-49d3-4c77-b683-2bede5a784f5-/app/core/target,target=/app/core/target \
+    bash core/scripts/build-cloud-sdk.sh
+
+FROM node AS dashboard
+RUN npm install --global pnpm@11.7.0
+WORKDIR /app/dashboard
+COPY dashboard/package.json dashboard/pnpm-lock.yaml dashboard/pnpm-workspace.yaml ./
+COPY dashboard/patches/ patches/
+COPY --from=sdk /app/core/crates/ployz-sdk /app/core/crates/ployz-sdk
+RUN --mount=type=cache,id=s/8089d161-49d3-4c77-b683-2bede5a784f5-/root/.local/share/pnpm/store,target=/root/.local/share/pnpm/store pnpm install --frozen-lockfile
+COPY dashboard/ ./
+# The SDK was built above; do not run package.json's combined Rust + Vite build.
+RUN pnpm build:app && pnpm prune --prod
+
+FROM node AS runtime
+RUN apt-get update \
+    && apt-get install -y --no-install-recommends ca-certificates git openssh-client \
+    && rm -rf /var/lib/apt/lists/*
+ENV NODE_ENV=production
+WORKDIR /app
+COPY --from=dashboard /app/dashboard/.output .output
+COPY --from=dashboard /app/dashboard/node_modules node_modules
+# The app's packaged SDK is the runtime copy; replace pnpm's source-tree link.
+RUN ln -sfn /app/.output/server/node_modules/@ployz/sdk node_modules/@ployz/sdk
+COPY dashboard/package.json dashboard/drizzle.config.ts ./
+COPY dashboard/drizzle/ drizzle/
+# Load the OpenTelemetry SDK before the app; it reads Railway's OTEL_* variables.
+CMD ["node", "--experimental-loader=@opentelemetry/instrumentation/hook.mjs", "--import", "@opentelemetry/auto-instrumentations-node/register", ".output/server/index.mjs"]

README.md

@@ -12,6 +12,7 @@ the same Cluster over SSH contexts. Neither is a control plane.
 ```text
 core/              Cargo workspace, installer, release scripts
 dashboard/         pnpm application; self-host/ holds the Compose deployment
+Dockerfile         Cloud image built from source; Railway builds branches with it
 Dockerfile.cloud   Cloud runtime image, packaged by the Cloud CI job
 scripts/           CI check selection
 .github/           Workflows

dashboard/README.md

@@ -48,7 +48,9 @@ what is missing or invalid.
 ## Build and deploy
 
 `pnpm build` compiles the native SDK and config WASM, then builds the web and
-Connect worker into `.output/`. `Dockerfile.cloud` packages both in one image:
+Connect worker into `.output/`. `Dockerfile.cloud` packages both in one image;
+the root `Dockerfile` builds the same image from source, so Railway can deploy
+any branch without CI:
 
 | Process | Start command | Healthcheck |
 | --- | --- | --- |