Stability chart is missing sub-0.5 day stability

> image1115×633 27.1 KB
> Here it says “7,889 cards with a `1~100` day stability”. However, memory stability can be <1. So either such cards are not included in the chart (they should be), or the text should say “`0.01~100 day`” instead.

Originally reported on https://forums.ankiweb.net/t/minor-issue-with-the-stability-chart/47419

Start by locating the stability chart and the code that produces its displayed day range or count. Check whether cards with sub-0.5-day stability are excluded; done means those cards are represented correctly or the chart text accurately states its lower bound.

Written by the indexing model from the issue text.