fix: Parquet nested values that span several pages #18407
Merged
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Fixes #18400.
This completely rewrites the logic that deal with decoding filtered nested values. This was needed to accommodate the fact that any kind of row value might span several data pages. This was not really accounted for in the previous implementation and where it worked, it was mostly by coincidence.
This also made it possible to add many fast paths for the decoder that were previously not there. Therefore, I think there are also some performance improvements here, but I am not sure how much.
I also wrote two tests to make sure that it actually works.