updated api paths

backend/api.py

@@ -55,7 +55,9 @@ from .g_cal import SCOPES, TOKEN_FILE
 
 CLIENT_ID = os.getenv("GOOGLE_CLIENT_ID")
 CLIENT_SECRET = os.getenv("GOOGLE_CLIENT_SECRET")
-BASE_URL = os.getenv("PUBLIC_BASE_URL", "http://localhost:8000")
+BASE_URL_RAW = os.getenv("PUBLIC_BASE_URL", "http://localhost:8000")
+BASE_URL = BASE_URL_RAW.rstrip("/")   # <— normalize, remove trailing slash
+
 REDIRECT_URI = f"{BASE_URL}/oauth/google/callback"
 
 def _client_config():