fixed missing nltk punkt

app.py

@@ -11,6 +11,7 @@ import matplotlib
 import joblib
 from sklearn.decomposition import PCA
 from collections import OrderedDict
+import nltk
 
 matplotlib.use("Agg")  # Use non-interactive backend
 import matplotlib.pyplot as plt
@@ -32,6 +33,8 @@ ANNOTATED_FEATURES_INFO = [
     "Colloquial | Formal",
 ]
 
+nltk.download("punkt_tab")
+
 # Load PCA model and annotated features
 try:
     pca = joblib.load(PCA_MODEL_PATH)