The accessibility-report recipe and its companion doc used "assistant.message.delta" (dotted), which never matches the SDK event. The canonical name is "assistant.message_delta" (underscore), as documented in instructions/copilot-sdk-nodejs.instructions.md and used by the Python cookbook. Without this fix the streaming branch was dead and no incremental output was printed.
(cherry picked from commit e050d7bfc96c55924b0bf534c8b3e57359463ba9)
Signed-off-by: syalioune <sy_alioune@yahoo.fr>
