Puzzle Storm stats show as "NaN" when user finishes attempt without solving any problems.

[dodekafonos]

Exact URL of where the bug happened

https://lichess.org/storm

Steps to reproduce the bug

1. Go to the "Puzzle Storm" page
2. Click "Finish try" (or press Enter) to end the current attempt
3. See the stats screen: it shows the values for "Precision", "Time" and "Time per move" as "NaN"

What did you expect to happen?

The "NaN" value should be treated to show as something else, more human friendly (such as "0" or "-")

What happened instead?

Stats appeared as "NaN"

Operating system

Windows 11 and Pop!_Os (Ubuntu 24.04)

Browser and version (or alternate access method)

Brave Browser

Additional information

I could fix this issue, however I'm not sure what would be the best value to show when no problems were solved.

[ddugovic]

Arguably, showing statistics isn't helpful when 0 puzzles were solved. It's possible NaN might be accurate.