fix: static build and debug entrypoint for synology

Dockerfile

@@ -1,28 +1,31 @@
 FROM node:20-slim AS frontend-builder
 WORKDIR /app/frontend
-
 COPY frontend-vite/package*.json ./
 RUN npm ci
-
 COPY frontend-vite/ .
 ENV NODE_ENV=production
 RUN npm run build
 
+# Use a builder with musl support for a truly static binary
 FROM rust:1.85-slim AS backend-builder
 WORKDIR /app/backend
 
-# Install build dependencies for Debian
 RUN apt-get update && apt-get install -y \
     pkg-config \
     libssl-dev \
-    libc6-dev \
+    musl-tools \
+    curl \
     && rm -rf /var/lib/apt/lists/*
 
+RUN rustup target add x86_64-unknown-linux-musl
+
 COPY backend-rust/Cargo.toml backend-rust/Cargo.lock ./
+# Pre-fetch dependencies
 RUN cargo fetch
 
 COPY backend-rust/ ./
-RUN cargo build --release --bin backend-rust
+# Build as a static binary
+RUN cargo build --release --target x86_64-unknown-linux-musl --bin backend-rust
 
 FROM python:3.11-slim-bookworm
 
@@ -36,19 +39,27 @@ RUN apt-get update && apt-get install -y \
 
 RUN pip install --no-cache-dir -U "yt-dlp[default]"
 
-COPY --from=backend-builder /app/backend/target/release/backend-rust /app/server
+# Copy the static binary
+COPY --from=backend-builder /app/backend/target/x86_64-unknown-linux-musl/release/backend-rust /app/server
 COPY --from=frontend-builder /app/frontend/dist /app/static
 
+# Create directories and set permissions
 RUN mkdir -p /tmp/spotify-clone-cache /tmp/spotify-clone-downloads && chmod 777 /tmp/spotify-clone-cache /tmp/spotify-clone-downloads
 
+# Add a debug entrypoint to catch early failures
+RUN echo '#!/bin/sh\n\
+echo "Starting container debug info..."\n\
+uname -a\n\
+ls -la /app/server\n\
+ldd /app/server || echo "Binary is static or ldd failed"\n\
+echo "Executing server..."\n\
+exec /app/server' > /app/entrypoint.sh && chmod +x /app/entrypoint.sh
+
 ENV PORT=8080
 ENV RUST_LOG=info
 
 EXPOSE 8080
 
-RUN chmod +x /app/server
-
-# Using root for compatibility with Synology permissions, change to USER 1000 if needed for security
 USER 0
 
-CMD ["/app/server"]
+ENTRYPOINT ["/app/entrypoint.sh"]