v0.8.4

In this version, we've changed the name of the setting:

OUTPUT_COLUMNS is now called OUTPUT_VARIABLES.

We've also updated the default value:

From [] (empty list) to None.

Rationale:

In the model, we use the word "variable" (like with the @variable() decorator). While "column" relates to table formats, it doesn’t cover all the ways we can show results. Changing the name to OUTPUT_VARIABLES helps keep things consistent throughout the model.

For the default value, using OUTPUT_VARIABLES=None is clearer because it means that no specific set of variables is chosen, so all variables will be included in the output. On the other hand, OUTPUT_VARIABLES=[] might suggest that no variables should be output at all, which could lead to confusion or extra checks in your code.