feat: Add python FFI interface and expose sqlite and duckdb table providers

[crystalxyz]

Expose table providers in Python via FFI

• Forked from Initial commit for python table providers #194 and fixed python dependencies

Summary

1. Created python subcrate for python-related development
2. Reorganized Cargo dependency and share common dependencies (arrow, datafusion, duckdb) in workspace cargo.toml
3. Implemented sqlite and duckdb table provider interfaces and tested in examples
4. Updated duckdbconn.rs to start new tokio runtime when triggered from PyO3
5. Updated Github CICD testing command

Testing

• Verified that all existing tests in Rust have passed
• Verified that Python examples can execute correctly via the following script:

cd python
maturin develop
cd examples
python3 duckdb_demo.py

Follow-up works

• Improve duckdb enum interface (ongoing)

The rest will be left for future works: #279

• Python ODBC table provider + example
• Python Postgres table provider + example
• Python MySQL table provider + example
• Integration testing
• Finalize Python interface design, i.e. new_memory() or new(":memory:")

[timsaucer]

Overall, this looks very nice. I suggest we merge this in but do not yet publish to pypi. There should be no breaking changes to the rust code, so anyone who depends on it should be okay. I think we will need to bump the minor version number if you haven't done so (I didn't check).

@phillipleblanc Would you be comfortable if we merged in partially complete work on the python side so we can have a series of smaller PRs until we're ready to publish?

[phillipleblanc]

Overall, this looks very nice. I suggest we merge this in but do not yet publish to pypi. There should be no breaking changes to the rust code, so anyone who depends on it should be okay. I think we will need to bump the minor version number if you haven't done so (I didn't check).

@phillipleblanc Would you be comfortable if we merged in partially complete work on the python side so we can have a series of smaller PRs until we're ready to publish?

Yes, that works for me - just mark this PR as ready to review and tag me when you are ready to merge. Thanks for working on this!

[crystalxyz]

@timsaucer @phillipleblanc This PR is ready for review!

[timsaucer]

I have just a couple of smaller suggestions. This feels like a huge leap forward in making these table providers accessible. I do recommend updating the title of this PR.

Also coming in DF 47, whenever it releases, we will have FFI catalog providers. Some of these interfaces might work well to support that as well. But that is future work. For now, this is excellent. Well done.

[phillipleblanc]

Thank you @CrystalZhou0529 and @timsaucer!