add p-table sort support

[stackoverfloweth]

noted in https://github.com/PrefectHQ/prefect/issues/7688 that our sort UX is not obvious to all users.

we expect that users would find it more obvious that clicking the header of a p-table column should try sorting.

we need to add styling (probably some sort of caret pointing up/down), p-table should emit something like @sort:key-asc. p-table column data needs a new property for something like sortable: true