The non-verbose EXPLAIN statement doesn't show optimized logical plan

[Dandandan]

Describe the bug
The EXPLAIN command is useful to show the plan of the query engine. However, the current output shows the un-optimized logical plan, which is not very useful as it maps almost 1:1 to the query.

To Reproduce

explain select price from example;
+--------------+--------------------------------------+
| plan_type    | plan                                 |
+--------------+--------------------------------------+
| logical_plan | Projection: #price                   |
|              |   TableScan: example projection=None |
+--------------+--------------------------------------+
1 rows in set. Query took 0 seconds.

Expected behavior
Explain without verbose should show a optimized non-verbose plan.

Additional context
Some other issues:
#219 (comment)
#96