Table definition extension

### Heterogeneous list based table definition

I am opening this PR to evaluate a possible extension to support a heterogeneous list definition of tables. The list of types would define the column type (and its nulability) and the column name.

I believe, due to work on my own projects, that defining collections in this way does offer extra type checking when "wiring" different system components together. I would also like to notice that, in zurihac's Data Haskell presentation, I was pleased to find out that other people in the haskell data processing space also implemented dataframe based on this representation. I think that if our ecosystem uses this kind of interface, data pipelining would be more ergonomic/safe.

I would like to know if this is something that can be implemented and if so I would like to try it out.

Thanks

Start by reviewing the existing table-definition API and its type representations in the beam codebase; the issue does not name files or tests. Determine whether heterogeneous lists can express column types, nullability, and names, then establish the supported design and validation criteria before attempting an implementation.

Written by the indexing model from the issue text.