Allow definition of "unique" property for tables to support single row updates

### Description

We currently support two actions on tables:

- `append` - which accepts a single row, or multiple rows of data and will add it to the existing table
- `replace` - whichever contents are provided, it will replace the entire table with the newly provided data.

An action we cannot support right now is replacing a single line, or multiple lines, without the need to replace the _entire_ table. In order to support this, we would need to have a way of each row having an "identifier" that should be unique to that row, then, when new data is passed, if that unique identifier matches any exiting rows - we replace it.

### Have you provided an initial effort estimate for this issue?

I have provided an initial effort estimate