[Joins] Add support for join keys with non-primitive dtypes for sort-merge join

[clarkzinzow]

Our sort-merge join currently only supports join keys with primitive dtypes - the Boundaries abstraction that we use to align joinable partitions convert upper/lower bounds to Python and do bound-comparisons in Python-land, which is only well-defined for basic dtypes.

We should port this Boundaries abstraction to Rust and leverage comparison semantics similar to our ColumnRangeStatistics, which we should support over as many of our dtypes as possible (especially temporal types).