"Trends" visualization (category time over time, per day/week)

I've long wanted a way to see the time spent per category over time, somewhat similar to the Timeline visualization (not the Timeline view), but instead of each bar being an hour, each bar would be a day/week.

I have plots like this in a notebook in https://github.com/ErikBjare/quantifiedme, but the notebooks are difficult to use and not very reliable. It would be really nice to see it in the main UI with some basic interactivity.

An example would be that you can select the 'Work' category and then see how many hours you've spent in that category each day for the last 30 days, possibly with an added moving average to keep track of long-term trends (as in my quantifiedme notebooks).

It has also been a highly requested feature on the forum: https://forum.activitywatch.net/t/day-wise-chart-for-specific-categories/639/3