Update app with proper token handling

app.py

@@ -18,9 +18,12 @@ logging.basicConfig(level=logging.INFO)
 logger = logging.getLogger(__name__)
 
 # Environment variables
-HF_TOKEN = os.getenv("HUGGING_FACE_TOKEN")
+HF_TOKEN = os.getenv("HUGGING_FACE_TOKEN", "v4e-o3_7lUO4cn8T9m9p5GNSI")  # Default to the token if not set in Space
 MODEL_NAME = os.getenv("MODEL_NAME", "google/gemma-2b-it")
 
+# Login to Hugging Face
+login(token=HF_TOKEN)
+
 # Create data directory for persistence
 DATA_DIR = os.path.join(os.path.dirname(os.path.abspath(__file__)), "data")
 os.makedirs(DATA_DIR, exist_ok=True)
@@ -110,9 +113,6 @@ class CodeReviewer:
     def initialize_model(self):
         """Initialize the model and tokenizer."""
         try:
-            if HF_TOKEN:
-                login(token=HF_TOKEN, add_to_git_credential=False)
-            
             logger.info("Loading tokenizer...")
             self.tokenizer = AutoTokenizer.from_pretrained(
                 MODEL_NAME,