Push down filter for Unnest plan

[jayzhan211]

Which issue does this PR close?

Closes #10935.

Rationale for this change

What changes are included in this PR?

Are these changes tested?

Are there any user-facing changes?

[alamb]

Thank you @jayzhan211 -- very nice. I had a suggestion for improving the docs, and I think we should add a few more test cases, but otherwise I think this is ready to go

[alamb]

Can you please also add a negative test with a predicate on uc2? Something like

explain select uc2 from (select unnest(column2) as uc2, column1 from v) where uc2  > 3;

it might also be good to add tests to actually run those queries

[jayzhan211]

We hadn't fix the comparison for unnest yet

query error DataFusion error: External error: Arrow error: Invalid argument error: Invalid comparison operation: List\(Field \{ name: "item", data_type: Int64, nullable: true, dict_id: 0, dict_is_ordered: false, metadata: \{\} \}\) > Int64
select uc2 from (select unnest(column2) as uc2, column1 from v) where uc2 > 3;

[jayzhan211]

I will leave the query in slt, and fix it in the follow up PR

[alamb]

This is a nice refactor. While reading it I figured it might also be nice to improve the documenatation

Suggested change

	/// return transformed projection plan and optinal filter's predicate
	/// Attempts to push `predicate` into a `FilterExec` below `projection
	///
	/// # Returns
	/// (plan, remaining_predicate)
	///
	/// `plan` is a LogicalPlan for `projection` with possibly a new FilterExec below it.
	/// `remaining_predicate` is any part of the predicate that could not be pushed down
	///
	/// # Example
	///
	/// Pushing a predicate like `foo=5 AND bar=6` with an input plan like this:
	///
	/// ```text
	/// Projection(foo, c+d as bar)
	/// ```
	///
	/// Might result in returning `remaining_predicate` of `bar=6` and a plan like
	///
	/// ```text
	/// Projection(foo, c+d as bar)
	/// Filter(foo=5)
	/// ...
	/// ```