feat(scaffold): add Dockerfile [skip ci]

Dockerfile

@@ -0,0 +1,20 @@
+# ---- Build stage ----
+FROM golang:1.22-alpine AS build
+WORKDIR /src
+
+COPY go.mod go.sum* ./
+RUN go mod tidy && go mod download
+
+COPY . .
+RUN CGO_ENABLED=0 GOOS=linux go build -trimpath -ldflags="-s -w" -o /app .
+
+# ---- Runtime stage (distroless) ----
+FROM gcr.io/distroless/static-debian12:nonroot
+COPY --from=build /app /app
+
+EXPOSE 8080
+
+HEALTHCHECK --interval=30s --timeout=5s --start-period=10s --retries=3 \
+    CMD ["/app", "-health-check"] 
+
+ENTRYPOINT ["/app"]