show source tables in information_schema.tables and show tables

[hzxa21]

After #7281, we treat materialized sources as tables in the syntax so I think it makes sense to also show them in information_schema.tables and show tables. Otherwise, BI tools such as superset won't be able to read information about the source tables and run queries on them.

[xxchan]

seems related #7344, maybe they should be handled together 🤔

[fuyufjh]

@xx01cyx Can you please take a look?

[xx01cyx]

This is already supported:

dev=> create table s1 (v int) with (
    connector = 'datagen'
) row format json;
CREATE_TABLE

dev=> show tables;
 Name 
------
 s1
(1 row)

dev=> SELECT * FROM information_schema.tables;
 table_catalog |    table_schema    |    table_name    |  table_type  | is_insertable_into 
---------------+--------------------+------------------+--------------+--------------------
 dev           | public             | s1               | BASE TABLE   | YES
 dev           | information_schema | columns          | SYSTEM TABLE | NO
 dev           | information_schema | tables           | SYSTEM TABLE | NO
 dev           | rw_catalog         | rw_meta_snapshot | SYSTEM TABLE | NO
 dev           | pg_catalog         | pg_attribute     | SYSTEM TABLE | NO
 dev           | pg_catalog         | pg_views         | SYSTEM TABLE | NO
 dev           | pg_catalog         | pg_database      | SYSTEM TABLE | NO
 dev           | pg_catalog         | pg_matviews      | SYSTEM TABLE | NO
 dev           | pg_catalog         | pg_collation     | SYSTEM TABLE | NO
 dev           | pg_catalog         | pg_keywords      | SYSTEM TABLE | NO
 dev           | pg_catalog         | pg_roles         | SYSTEM TABLE | NO
 dev           | pg_catalog         | pg_operator      | SYSTEM TABLE | NO
 dev           | pg_catalog         | pg_type          | SYSTEM TABLE | NO
 dev           | pg_catalog         | pg_cast          | SYSTEM TABLE | NO
 dev           | pg_catalog         | pg_user          | SYSTEM TABLE | NO
 dev           | pg_catalog         | pg_class         | SYSTEM TABLE | NO
 dev           | pg_catalog         | pg_settings      | SYSTEM TABLE | NO
 dev           | pg_catalog         | pg_namespace     | SYSTEM TABLE | NO
 dev           | pg_catalog         | pg_index         | SYSTEM TABLE | NO
 dev           | pg_catalog         | pg_opclass       | SYSTEM TABLE | NO
 dev           | pg_catalog         | pg_tablespace    | SYSTEM TABLE | NO
 dev           | pg_catalog         | pg_stat_activity | SYSTEM TABLE | NO
 dev           | pg_catalog         | pg_enum          | SYSTEM TABLE | NO
 dev           | pg_catalog         | pg_shdescription | SYSTEM TABLE | NO
 dev           | pg_catalog         | pg_attrdef       | SYSTEM TABLE | NO
 dev           | pg_catalog         | pg_description   | SYSTEM TABLE | NO
 dev           | pg_catalog         | pg_am            | SYSTEM TABLE | NO