Returns a bounded page of the active attempt's redacted system events. Poll with the returned opaque cursor to receive only new events. When hasMore is true, more events are already stored; read the next page without waiting. Empty pages preserve the cursor, and the response explicitly reports gaps or unavailable event history. Clients that advertise event_too_large in X-Tessl-Launch-Event-States receive a permanent event_too_large result that preserves the cursor. Its archive is downloadable only when its state is available; pending archives become usable after confirmation. Other clients receive a terminal gap so they do not retry an unknown state.