Add support for CORRESPONDING option in set operations

[ebyhr]

Description

Add support for CORRESPONDING option in set operations.
The option matches columns by name instead of by position:

SELECT * FROM (VALUES (1, 'alice')) AS t(id, name)
UNION ALL CORRESPONDING
SELECT * FROM (VALUES ('bob', 2)) AS t(name, id);

 id | name
----+-------
  1 | alice
  2 | bob
(2 rows)

The option is defined in SQL spec

<query expression body> ::=
    <query term> 
  | <query expression body>  UNION [ ALL | DISTINCT ]
      [ <corresponding spec>  ] <query term> 
  | <query expression body>  EXCEPT [ ALL | DISTINCT ]
      [ <corresponding spec>  ] <query term> 

<query term> ::=
    <query primary> 
  | <query term>  INTERSECT [ ALL | DISTINCT ]
      [ <corresponding spec>  ] <query primary> 

<corresponding spec> ::=
  CORRESPONDING [ BY <left paren>  <corresponding column list>  <right paren>  ]

Release notes

## General
* Add support for the `CORRESPONDING` option in set operations. ({issue}`issuenumber`)

[ebyhr]

Changing to draft as I missed logic to handle different number of columns between left and right relations.

[martint]

Using a boolean is not going to be sufficient for modeling the list of columns in the CORRESPONDING clause. It will require a bigger change later.

Add support for passing in the list of columns in the grammar and AST, even if, for the first version, the analyzer rejects any queries where the list is provided.

[martint]

The planner should not be doing any mappings based on names. That should have been established during analysis, and any necessary supporting data structure recorded in the Analysis object. E.g., a list of fields to select in the order in which they should be considered + the corresponding relation types.

[martint]

How does this handle standard SQL identifier canonicalization and matching?