feat(add_task): Add "AI-generated" note

Signed-off-by: Marcel Klehr <mklehr@gmx.net>

Author: marcelklehr

ex_app/lib/all_tools/calendar.py

@@ -201,11 +201,13 @@ def add_task(calendar_name: str, title: str, description: str, due_date: Optiona
 		:return: bool
 		"""
 
+		description_with_ai_note = f"{description}\n\n---\n\nThis task was scheduled by Nextcloud AI Assistant."
+
 		# Create task
 		c = Calendar()
 		t = Todo()
 		t.name = title
-		t.description = description
+		t.description = description_with_ai_note
 
 		# Parse date and times
 		if due_date: