add dockerfile to serve content on port 3000

add a println! statement to check that the service starts serving

Dockerfile

@@ -0,0 +1,9 @@
+FROM rust:1.75.0
+
+WORKDIR /usr/src/chaospott-status
+COPY . .
+RUN cargo install --path .
+
+EXPOSE 3000
+
+CMD ["chaospott-status"]