refactor: use proper Docker build outputs

Author: kdkasad

Software/Dockerfile

@@ -31,5 +31,12 @@ COPY . .
 
 # Build for Raspberry Pi (no-default-features to skip druid/GUI)
 RUN cargo build --release --target aarch64-unknown-linux-gnu --no-default-features --features real
+RUN aarch64-linux-gnu-strip /app/target/aarch64-unknown-linux-gnu/release/phone-bell-software
 
 # The binary will be at /app/target/aarch64-unknown-linux-gnu/release/phone-bell-software
+
+FROM scratch
+COPY --from=builder /app/target/aarch64-unknown-linux-gnu/release/phone-bell-software /phone-bell-software-arm64
+ENTRYPOINT ["/phone-bell-software-arm64"]
+
+# The binary will be at /phone-bell-software-arm64 in the output image

Software/build-rpi.sh

@@ -4,16 +4,6 @@ set -e
 cd "$(dirname "$0")"
 
 echo "Building Docker image..."
-docker build -t phone-bell-builder .
-
-echo "Extracting binary..."
-docker create --name phone-bell-temp phone-bell-builder
-docker cp phone-bell-temp:/app/target/aarch64-unknown-linux-gnu/release/phone-bell-software ./phone-bell-software-arm64
-docker rm phone-bell-temp
-
-echo "Stripping debug symbols..."
-docker run --rm -v "$(pwd):/out" phone-bell-builder \
-  aarch64-linux-gnu-strip -o /out/phone-bell-software-arm64 /out/phone-bell-software-arm64
-
+docker build -o . .
 echo "Done! Binary: phone-bell-software-arm64"
 ls -lh phone-bell-software-arm64