feat: information schema support (#71)

* Add information_schema support and enhance PostgreSQL compatibility\n\n- Added , , and  in  for schema introspection using DataFusion catalogs.\n- Integrated  queries in  with , , and .\n- Implemented mock  in  to return , improving  compatibility.\n- Enhanced  with  support, returning  as the search path.\n- Refined query qualification in  to exclude  and , preventing planning errors.\n- Added debug logging in  for incoming queries (requires  dependency).\n- Updated  with basic table registration and catalog name handling, setting the stage for further enhancements.\n- Updated  to include  dependency for debugging.\n\nNote:  still uses  and lacks  integration; to be addressed in a future commit.

* test: fix dbname in integration test

* doc: update status in readme

* fix: remove query normalization step

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Co-authored-by: Oluwapeluwa Ibrahim <[email protected]>
Co-authored-by: Ibrahim Oluwapeluwa <[email protected]>

Author: sunng87

Cargo.lock

@@ -19,7 +19,7 @@ picking up unfinished items.
 
 - [x] datafusion-postgres as a CLI tool
 - [x] datafusion-postgres as a library
-- [ ] datafusion information schema: a postgres compatible `information_schema`
+- [x] datafusion information schema: a postgres compatible `information_schema`
 - [ ] datafusion pg catalog: a postgres compatible `pg_catalog`
 - [ ] data type mapping between arrow and postgres: in progress
 - [ ] additional postgres functions for datafusion