fix: add type annotations to PermissionBits

backend/src/v1/inbox_messages/schemas.py

@@ -9,9 +9,9 @@ from pydantic import BaseModel, ConfigDict
 
 
 class PermissionBits:
-    VIEW = 1  # 001
-    INVITE = 2  # 010
-    EDIT = 4  # 100
+    VIEW: int = 1  # 001
+    INVITE: int = 2  # 010
+    EDIT: int = 4  # 100
 
     @classmethod
     def encode(cls, view: bool, edit: bool, invite: bool) -> int: