Support Pre-aggregation incremental refreshKey with different time dimension than cube timeDimension

Is your feature request related to a problem? Please describe. When using incremental pre aggregation building, with update window, we are forced to use the "official" time dimension of the cube(Lets call it "start_time". This is good for most cases, but when i want to import old data with old "start_time" i can't pre-aggregate it and i'm forced to change the refresh key manually. this is because old start_time is not in in update_window.

Describe the solution you'd like My suggestion is to add an option for different sql column to be used for update window sql(lets call it "insertion_time"). in this case you can import data with any date, and it will build the relevant pre aggregations.

Describe alternatives you've considered Support "sql" property for updateWindow refreshKey.

Additional context Mostly in slack when people ask about this problem, answer is change you refresh key, import the data and then change it back to original state.