feat(docker): non-root user + ENTRYPOINT (OwO-Network#222)

Closes OwO-Network#221.

- Run as non-root using an Alpine system account (UID auto-assigned from the 100-999 system range, referenced by name to avoid hard-coding).
- Replace CMD with ENTRYPOINT so args passed to `docker run` flow through to the deeplx binary.
- EXPOSE 1188 for documentation.

Author: danny900714

Dockerfile

@@ -6,5 +6,8 @@ RUN CGO_ENABLED=0 go build -a -installsuffix cgo -o deeplx .
 
 FROM alpine:latest
 WORKDIR /app
-COPY --from=builder /go/src/github.com/OwO-Network/DeepLX/deeplx /app/deeplx
-CMD ["/app/deeplx"]
+RUN addgroup -S deeplx && adduser -h /app -G deeplx -SH deeplx
+USER deeplx:deeplx
+COPY --from=builder --chown=deeplx:deeplx /go/src/github.com/OwO-Network/DeepLX/deeplx /app/deeplx
+EXPOSE 1188
+ENTRYPOINT ["/app/deeplx"]