fix: create /data/redis directory at runtime to handle HF persistent volume mount shadowing

Dockerfile

@@ -73,6 +73,6 @@ HEALTHCHECK --interval=30s --timeout=10s --start-period=60s --retries=3 \
 # HuggingFace Spaces port
 EXPOSE 8080
 
-# Startup: start Redis → run Alembic migrations → start Uvicorn
-CMD ["sh", "-c", "redis-server /app/redis.conf && sleep 1 && alembic upgrade head && uvicorn app.main:app --host 0.0.0.0 --port 8080 --workers 2 --loop uvloop --http httptools"]
+# Startup: create redis data dir → start Redis → run Alembic migrations → start Uvicorn
+CMD ["sh", "-c", "mkdir -p /data/redis && redis-server /app/redis.conf && sleep 1 && alembic upgrade head && uvicorn app.main:app --host 0.0.0.0 --port 8080 --workers 2 --loop uvloop --http httptools"]