Photon now exposes attachment send (Ray Sun, photon-nousresearch), so
the Photon plugin gains outbound media to match the BlueBubbles iMessage
channel.
- sidecar: new /send-attachment endpoint wrapping space.send(attachment())
/ space.send(voice()); caption sent as a trailing text bubble.
- adapter: override send_image/send_image_file/send_voice/send_video/
send_document/send_animation. URL helpers cache to a local path first
(cache_image_from_url), file helpers pass through. Defense-in-depth
path re-validation before the path reaches the Node sidecar.
- _standalone_send (cron): send text first, then each media_file as a
/send-attachment call (is_voice -> voice builder).
- docs/README: flip the 'outbound attachments not wired' note.