Method iter_tile_versions

nodedb/src/engine/array/memtable/tile_buffer.rs:300–309

Returns an iterator over all tile versions for `hilbert_prefix` whose `system_from_ms <= system_as_of`, ordered **newest-first**. Used by the bitemporal ceiling resolver in DP read handlers.

(
        &self,
        hilbert_prefix: u64,
        system_as_of: i64,
    )

    ///
    /// Used by the bitemporal ceiling resolver in DP read handlers.
    pub fn iter_tile_versions(
        &self,
        hilbert_prefix: u64,
        system_as_of: i64,
    ) -> impl Iterator<Item = (TileId, &TileBuffer)> {
        use nodedb_array::types::TileId as Tid;
        let lo = Tid::new(hilbert_prefix, i64::MIN);
        let hi = Tid::new(hilbert_prefix, system_as_of);
        self.tiles.range(lo..=hi).rev().map(|(&id, buf)| (id, buf))
    }
}

/// One flushed tile record — returned to the flush path so it can build