Fix IndexError in folder namespace page_get_language method

Co-authored-by: TrueBrain <[email protected]>

Author: Copilot

truewiki/namespaces/folder/namespace.py

@@ -90,7 +90,10 @@ def page_get_language(cls, page: str) -> Optional[str]:
         if cls._is_namespace_root(page):
             return None
 
-        return page.split("/")[2]
+        spage = page.split("/")
+        if len(spage) < 3:
+            return None
+        return spage[2]
 
     @staticmethod
     def get_used_on_pages(page: str) -> list: