Fix: remove unsupported --model arg from prepare_data.py call

run.sh

@@ -31,9 +31,7 @@ echo ""
 if [ "${SKIP_PREP:-0}" = "0" ]; then
     echo "━━━ Stage 1: Data Preparation ━━━"
     python /app/prepare_data.py \
-        --output-dir "$DATA_DIR" \
-        --model "$MODEL" \
-        --model "$MODEL"
+        --output-dir "$DATA_DIR"
     echo "✅ Data prepared in $DATA_DIR"
 else
     echo "⏭  Skipping data preparation (SKIP_PREP=1)"