A direct answer to your question is to use an arrayformula.
But… do you actually need the result of the formula in the Google Sheet, or will it just be used in your app?
If you don’t need it in the sheet, then you are much better off performing the calculation in Glide using computed columns.
You should be able to create a template column in both the Weeks table and the Priorities table that joins the Creator column value to the Week Name column value. Then create a relation column that links the template in the Weeks table to the template in the Priorities table. Finally create a Rollup column that uses the relation to sum the matching values from the Priority Minutes column.