feat: add warning about context_chat not respecting files_accesscontrol rules

Signed-off-by: Julien Veyssier <julien-nc@posteo.net>

Author: julien-nc

admin_manual/file_workflows/access_control.rst

@@ -8,6 +8,9 @@ rules. If all rules of a group hold true, the group matches the request and
 access is being denied. The rules criteria range from IP address, to user
 groups, collaborative tags and :ref:`some more <available-rules-label>`.
 
+.. note:: Keep in mind that Context Chat is not affected by the File Access Control rules
+    and will index files which access is denied by a rule.
+
 Denied access
 -------------