//! [`Node`] — a graph vertex with a stable ULID identity, labels, and properties.
use ;
use ;
/// A node (vertex) in the property graph.
///
/// Nodes are identified by a [`NodeId`] (ULID), may carry one or more string
/// labels (e.g. `"Person"`, `"Company"`), and hold an arbitrary key-value
/// [`Properties`] map.
///
/// `PartialEq` is derived for testing; production code should compare by `id`.