Update Dockerfile

Dockerfile

@@ -26,11 +26,19 @@ RUN pip install --no-cache-dir --upgrade pip && \
     pip install --no-cache-dir -r requirements.txt
 
 # Pre-download the SentenceTransformer embedding model to avoid runtime cold-starts
-RUN HF_TOKEN=$HF_TOKEN HUGGINGFACEHUB_API_TOKEN=$HF_TOKEN HUGGINGFACE_HUB_TOKEN=$HF_TOKEN \
-    python - <<'PY'
+RUN if [ -z "$HF_TOKEN" ]; then \
+        echo "HF_TOKEN build arg is required to download google/embeddinggemma-300m" >&2; \
+        exit 1; \
+    fi && \
+    HF_TOKEN=$HF_TOKEN python - <<'PY'
+import os
 from sentence_transformers import SentenceTransformer
 
-SentenceTransformer("google/embeddinggemma-300m")
+token = os.environ.get("HF_TOKEN")
+if not token:
+    raise SystemExit("HF_TOKEN environment variable missing during build")
+
+SentenceTransformer("google/embeddinggemma-300m", use_auth_token=token)
 PY
 
 # Copy the rest of the application code