Replace the Notify.Events delivery with a Google Chat space webhook. The
automation builds a cardsV2 card (printer/event header, print details,
camera snapshot, Open printer button) and falls back to plain text if
Google rejects the card or the request fails.
Adds rest_command.google_chat_octoeverywhere, which needs
google_chat_octoeverywhere_webhook in secrets.yaml on the host. The
notify_event_octoeverywhere_token secret is no longer used.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>