feat(cypher): add support for return nodes

[aheev]

Achieved returning full node objects by expanding to all properties in logical_plan. Also added unit and system tests

Closes #110

[aheev]

@ChunxuTang could you PTAL?

[ChunxuTang]

@ChunxuTang could you PTAL?

Sure, thanks for the work! I'll take a look in the following few days.

[codecov-commenter]

Codecov Report

❌ Patch coverage is 95.45455% with 7 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
crates/lance-graph/src/logical_plan.rs	95.42%	7 Missing ⚠️

📢 Thoughts on this report? Let us know!

[ChunxuTang]

@aheev Thanks for the contribution! It generally looks good to me.
Could you fix the CI errors?

[ChunxuTang]

Thanks for the update!
Just left a minor comment.

[ChunxuTang]

Thanks for the update! LGTM.

Let me re-trigger the workflows to make sure everything is working well.

[aheev]

nightly build failed with

   Compiling shellexpand v3.1.1
error[E0308]: mismatched types
   --> /home/runner/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/shellexpand-3.1.1/src/funcs.rs:395:21
    |
394 |                 let var_name = match var_name.as_str() {
    |                                      ----------------- this expression has type `&str`
395 |                     Some(var_name) => var_name,
    |                     ^^^^^^^^^^^^^^ expected `str`, found `Option<_>`
    |
    = note: expected type `str`
               found enum `Option<_>`
...

Some issue with shellexpand installation