feat(python): Implement bindings to IPC writer

[paleolimbot]

This PR implements bindings to the IPC writer in the nanoarrow C library. This adds:

• An ipc.StreamWriter() class roughly mirroring pyarrow's ipc.Stream()
• Schema.serialize() and Array.serialize() to match pyarrow's serialize() methods.

import io
import nanoarrow as na 
from nanoarrow.ipc import StreamWriter, InputStream

out = io.BytesIO()
writer = StreamWriter.from_writable(out)
writer.write_stream(InputStream.example())

na.Array(InputStream.from_readable(out.getvalue()))
#> nanoarrow.Array<non-nullable struct<some_col: int32>>[3]
#> {'some_col': 1}
#> {'some_col': 2}
#> {'some_col': 3}

[jorisvandenbossche]

Looks good!
Added some minor comments/questions, didn't go through everything, but already posting what I have for today

[jorisvandenbossche]

I suppose using bytes | None is only allowed if not supporting older versions of python?

[paleolimbot]

I think Optional is OK but | is 3.10 or higher (we should be using Optional everywhere but I didn't know about it when I started writing type hints. At some point we can go back and change them all).

[jorisvandenbossche]

Add a class docstring for Writer?

[jorisvandenbossche]

Also, to understand a bit the different classes here. The already existing Stream object is essentially the "reader" equivalent?

And for this writer, does that only support the stream format or also the file format?

[paleolimbot]

Stream is a bit of a compromise...we can't just "subclass a record batch reader" like is done in Arrow C++/Pyarrow, but we need a place to put the code that deals with file IO...so the stream is sort of an internal stepping stone to eliminate anything dealing with files in nanoarrow.array_stream.ArrayStream. It should have a better name now that its purpose is more clear.

Writer is definitely a user-facing concept and should probably be a StreamWriter (since it doesn't do files)

[jorisvandenbossche]

There could in theory also be a write_array (or maybe rather write_batch) method that takes a single array to write to the stream?

[paleolimbot]

There could be! An array can be implicitly converted to a stream and will work here, but I'll add one for symmetry (and some day it might be faster!)