fix: disable bcrypt truncate error

auth.py

@@ -16,8 +16,8 @@ from jose import JWTError, jwt
 from pydantic import BaseModel
 
 
-# Password hashing
-pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")
+# Password hashing (truncate_error=False allows bcrypt to silently truncate)
+pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto", bcrypt__truncate_error=False)
 
 # JWT settings
 ALGORITHM = "HS256"
@@ -93,14 +93,19 @@ def save_users(data_dir: Path, users: dict[str, dict]):
         json.dump(users, f, indent=2)
 
 
+def truncate_password(password: str) -> str:
+    """Truncate password to 72 bytes for bcrypt."""
+    return password.encode('utf-8')[:72].decode('utf-8', errors='ignore')
+
+
 def hash_password(password: str) -> str:
     """Hash a password (truncate to 72 bytes for bcrypt)."""
-    return pwd_context.hash(password[:72])
+    return pwd_context.hash(truncate_password(password))
 
 
 def verify_password(plain_password: str, hashed_password: str) -> bool:
     """Verify a password against its hash."""
-    return pwd_context.verify(plain_password[:72], hashed_password)
+    return pwd_context.verify(truncate_password(plain_password), hashed_password)
 
 
 def create_user(data_dir: Path, username: str, password: str, email: Optional[str] = None) -> User: