New optional note field created_by (kuhy|claude), stored like by/repo and
omitted when unset so older builds stay wire-compatible. App UI stamps kuhy;
MCP add_task and the CLI stamp claude. list/get/search output includes it.
Human notes sort above Claude's; Claude notes are hidden behind a per-device
eye toggle. CLI --backfill-created-by [--dry-run] classifies old notes by the
node that wrote created_at, writing only the created_by field.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
