Entire annotation structure is now persistent, remove _p_changed.

Author: gbastien

CHANGES.rst

@@ -39,6 +39,7 @@ Changelog
 - Fixed faceted viewlet broken because sessions format changed from list to OrderedDict.
   [gbastien]
 - Turned file info in session annotation from `dict` to `PersistentMapping`.
+  Entire annotation structure is now persistent, remove `_p_changed`.
   [gbastien]
 
 1.0a2 (2026-02-06)

src/imio/esign/utils.py

@@ -119,7 +119,6 @@ def add_files_to_session(
         if u"{session_id}" in session["title"]:
             session["title"] = session["title"].replace(u"{session_id}", str(session_id))
     session["last_update"] = datetime.now()
-    annot._p_changed = True
     return session_id, session