pass write result to on_write_complete

[chenkovsky]

Why are these changes needed?

Currently, Datasink will ignore the result of write. It's hard to implement commit logic in on_write_complete.
This PR refactors plan_write_op and changes typing for write & on_write_complete. data sink can pass result of write to on_write_complete

Related issue number

Closes #48933

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  • I've added any new APIs to the API Reference. For example, if I added a
    method in Tune, I've added it in doc/source/tune/api/ under the
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• Testing Strategy
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  • This PR is not tested :(

[raulchen]

hi @chenkovsky sorry for the delayed review.
One problem with the PR is that certain optimization rules depend on the write op to have 2 separate MapTransformFns: write and stats.
Also I plan to make some minor changes to the DataSink interface.
I'll submit a new PR to address this issue soon.

[raulchen]

@chenkovsky #49251 is the new PR

[chenkovsky]

@chenkovsky #49251 is the new PR

@raulchen
awesome, your PR has clear generic typing. it looks pretty good.