feat(chain)!: Change `TxGraph` to understand evicted-at & last-evicted

feat(chain)!: Change `TxGraph` to understand evicted-at & last-evicted

The evicted-at and last-evicted timestamp informs the `TxGraph` when the
transaction was last deemed as missing (evicted) from the mempool.

The canonicalization algorithm is changed to disregard transactions with
a last-evicted timestamp greater or equal to it's last-seen timestamp.
The exception is when we have a canonical descendant due to rules of
transitivity.

Update rusqlite_impl to persist `last_evicted`.

Also update docs:
* Remove duplicate paragraphs about `ChangeSet`s.
* Add "Canonicalization" section which expands on methods that require
  canonicalization and the associated data types used in the
  canonicalization algorithm.