[#55776] create proxy without static assets (#83)

* [#55776] added custom image for proxy

- based on caddy:2
- copy assets from openproject image into proxy image

* [#55776] removed static asset serving from proxy

- https://community.openproject.org/wp/55776
- apparently caddy correctly redirects asset requests to the web service

compose/proxy/Dockerfile

@@ -0,0 +1,8 @@
+FROM caddy:2
+
+COPY ./Caddyfile.template /etc/caddy/Caddyfile.template
+
+ARG APP_HOST
+RUN sed 's|${APP_HOST}|'"$APP_HOST"'|g' /etc/caddy/Caddyfile.template > /etc/caddy/Caddyfile
+
+ENTRYPOINT ["caddy", "run", "--config", "/etc/caddy/Caddyfile"]