In my team we used a shared Excel file, with one sheet per customer, and roughly every row would be one query. We'd have some columns reserved for notes, exampl

In my team we used a shared Excel file, with one sheet per customer, and roughly every row would be one query. We'd have some columns reserved for notes, example outputs and links to email threads etc. with more context. The main drawback is that some rows would start to get lengthy since we'd add more and more links, but overall worked quite well. Excel has some neat features, for example you can have a set of queries per customer that contain e.g. their office address, and then use a string replace formula to generate the same set of queries for another customer.