Add arrow cast

[kosiew]

Which issue does this PR close?

Completes a task in #463

Rationale for this change

This PR introduces the implementation of the arrow_cast function from datafusion's similar arrow_cast function.

What changes are included in this PR?

Functionality:

Implements the arrow_cast function

Tests:

Adds a test case to validate the functionality of arrow_cast.

Are there any user-facing changes?

Yes, this PR adds the arrow_cast function to the API, enabling users to columns into specific data type.

[timsaucer]

Thank you for the additions. Do you think this is needed or to just use Expr.cast?

[kosiew]

Thank you for the additions. Do you think this is needed or to just use Expr.cast?

[timsaucer]

So doing a little testing to see if this is necessary:

from datafusion import SessionContext, col, lit
import pyarrow as pa
import datetime
ctx = SessionContext()

df = ctx.from_pydict({
    "a": pa.array([1], type=pa.int64()),
    "date": pa.array([datetime.datetime.today()], type=pa.timestamp("us")),
})

df.show()
print(df.schema())

df = (
    df
    .with_column("b", col("a").cast(pa.int8()))
    .with_column("ms_date", col("date").cast(pa.timestamp("ms")))
)

df.show()
print(df.schema())

Produces:

DataFrame()
+---+----------------------------+
| a | date                       |
+---+----------------------------+
| 1 | 2024-12-12T07:28:24.431099 |
+---+----------------------------+
a: int64
date: timestamp[us]
DataFrame()
+---+----------------------------+---+-------------------------+
| a | date                       | b | ms_date                 |
+---+----------------------------+---+-------------------------+
| 1 | 2024-12-12T07:28:24.431099 | 1 | 2024-12-12T07:28:24.431 |
+---+----------------------------+---+-------------------------+
a: int64
date: timestamp[us]
b: int8
ms_date: timestamp[ms]

So maybe we can use the existing method?

[kosiew]

@timsaucer ,

Thanks for the detailed example.

The other reason for this PR is also to add arrow_cast so that the full set of datafusion Rust scalar functions are available in datafusion-python - #463