List Gmail inbox

List the messages on the first page of the Gmail inbox. Requires an authenticated mail.google.com session. Returns folder, total (the range line as rendered, e.g. "1–50 of 240") and rows of sender, subject, snippet, date plus the unread / starred / hasAttachment flags. Covers only the first inbox page (up to ~50 rows as Gmail renders it); there is no pagination. Be aware that the output requires at least one row, so a genuinely empty inbox is not representable and will surface as a failure rather than an empty list.