fix(docker): add libsndfile to Alpine image for audio processing (#18092)

ARM64 Alpine image was missing libsndfile library causing soundfile
module to fail with "cannot load library" error.

Author: Chesars

docker/Dockerfile.alpine

@@ -34,8 +34,8 @@ RUN pip wheel --no-cache-dir --wheel-dir=/wheels/ -r requirements.txt
 # Runtime stage
 FROM $LITELLM_RUNTIME_IMAGE AS runtime
 
-# Update dependencies and clean up
-RUN apk upgrade --no-cache
+# Update dependencies and clean up, install libsndfile for audio processing
+RUN apk upgrade --no-cache && apk add --no-cache libsndfile
 
 WORKDIR /app