Function append_memory 

pub fn append_memory(
    commands: Commands<'_, '_>,
    settled: Query<'_, '_, (Entity, &RunOf, &Conversation), NeedsMemoryAppend>,
    memories: Query<'_, '_, &Remembers>,
    bound: Query<'_, '_, &Bound>,
    children: Query<'_, '_, &Children>,
    utterances: Query<'_, '_, (Entity, Has<Remembered>), With<Utterance>>,
    content: ContentGraph<'_, '_>,
)

Schedule a settled remembering run’s ordered, nonremembered utterances for memory append. Content errors fail the run. A persisted marker prevents scheduling a second append after checkpoint restoration.