build: Dockerfile that expects ready baked binaries

Dockerfile.buildx

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+FROM alpine
+ARG TARGETARCH
+
+EXPOSE 8384 22000 21027/udp
+
+VOLUME ["/var/syncthing"]
+
+RUN apk add --no-cache ca-certificates su-exec tzdata
+
+COPY ./syncthing-linux-$TARGETARCH /bin/syncthing
+COPY ./script/docker-entrypoint.sh /bin/entrypoint.sh
+
+ENV PUID=1000 PGID=1000 HOME=/var/syncthing
+
+HEALTHCHECK --interval=1m --timeout=10s \
+  CMD nc -z 127.0.0.1 8384 || exit 1
+
+ENV STGUIADDRESS=0.0.0.0:8384
+ENTRYPOINT ["/bin/entrypoint.sh", "/bin/syncthing", "-home", "/var/syncthing/config"]