refactor: unify config and data structures

Dockerfile

@@ -18,13 +18,16 @@ WORKDIR /app
 COPY --from=builder /bin/davserver /usr/local/bin/davserver
 COPY --from=builder /bin/nidusctl /usr/local/bin/nidusctl
 
-# Default data and config locations
+# Default data location
 VOLUME ["/app/data"]
-# config.yaml itself is git-ignored (it holds real secrets), so the image
-# ships the example config as a working default; mount your own
-# config.yaml over /app/config.yaml (see docker-compose.yaml) to override it.
-COPY config.example.yaml /app/config.yaml
+
+# environment variables (override as needed)
+ENV NIDUS_DATA_DIR=/app/data
+ENV NIDUS_HOST=0.0.0.0
+ENV NIDUS_PORT=8080
+ENV NIDUS_LOG_LEVEL=warn
+ENV NIDUS_LOG_FORMAT=text
 
 EXPOSE 8080
 
-ENTRYPOINT ["davserver", "-config", "/app/config.yaml"]
+ENTRYPOINT ["davserver"]