Maintenance

A list with no connection does not refresh itself

That is the cost of not handing over account access, and it is worth planning for rather than being surprised by.

Two habits cover almost everything. When you start a new subscription, add it then — it takes less time than finding it later. When a price changes and you notice, edit the line.

Beyond that, a fresh screenshot every few months rebuilds the picture from scratch. That is also the only way to see a change over time, since there is no price history kept anywhere.

A connected app would refresh without being asked. It would also hold a permission to your account indefinitely. This is the other side of that trade, stated plainly.