Add types for p-table body template context

[bahuma20]

Problem

When using the p-table component with a custom body template, and binding the $implicit to let-product, the product variable has the type any.

It would be good if we could somehow automatically set the type of $implicit to the row type.

Why is this useful

Types would have the benefit of ensuring consistency in updates of PrimeNG and Angular itself and would enable code completion.

Example

I have forked the basic Table example from the documentation, and edited the output of the first column to point to a non-existent property.

I would expect that the angular build fails with a compilation error. But it does build sucessfully without any problem, because the type of the product variable is any.

https://stackblitz.com/edit/jmmphv?file=src%2Fapp%2Ftable-basic-demo.html

Workaround

There is a workaround by Alain Boudard on medium.com, where he uses an additional custom directive on the ng-template for the body, which overrides the context: https://coco-boudard.medium.com/typing-angular-primeng-templates-7c2851f76c39

But in my opinion, PrimeNG should set the correct type automatically, by defining a correct templateContext instead of any.