add healthcheck service

dockers/both/Dockerfile

@@ -14,6 +14,12 @@ RUN --mount=type=cache,target=/go/pkg/mod/ \
     go mod download -x && go mod verify
 COPY . .
 
+FROM base as build-utils
+RUN --mount=type=cache,target=/go/pkg/mod/ \
+  go build \
+  -o /go/bin/utils \
+  /go/src/git.loyso.art/frx/devsim/cmd/utility/main.go
+
 FROM base as build-web
 RUN --mount=type=cache,target=/go/pkg/mod/ \
   go build \
@@ -30,10 +36,17 @@ FROM gcr.io/distroless/static-debian12@sha256:ce46866b3a5170db3b49364900fb3168dc
 
 WORKDIR /app
 COPY --from=build-web /go/bin/web /app/web
+COPY --from=build-utils /go/bin/utils /app/utils
 
 ENV DEVSIM_HTTP_ADDR=":80"
 EXPOSE 80
 
+ENV DEVSIM_MONITOR_ADDR=":8080"
+EXPOSE 8080
+
+HEALTHCHECK --interval=10s --timeout=3s \
+   CMD ["/app/utils", "health"]
+
 ENTRYPOINT ["/app/web"]
 
 FROM gcr.io/distroless/static-debian12@sha256:ce46866b3a5170db3b49364900fb3168dc0833dfb46c26da5c77f22abb01d8c3 as migrator