+/**
+ * The `Listen` trait is used to notify when blocks have been connected or disconnected from the
+ * chain.
+ *
+ * Useful when needing to replay chain data upon startup or as new chain events occur. Clients
+ * sourcing chain data using a block-oriented API should prefer this interface over [`Confirm`].
+ * Such clients fetch the entire header chain whereas clients using [`Confirm`] only fetch headers
+ * when needed.
+ */