Replace LazyFrame.collect with LazyFrame.collect_stream

[ion-elgreco]

If polars ever adds a LazyFrame.collect_stream() then we can pipe that into delta-rs directly.

[gfvioli]

Is the recent addition of LazyFrame.{sink,collect}_batches revelant for this issue? Sounds to me like this feature could be a go now.

pola-rs/polars#23980