jackaloissteam-cloud/time-keeper-pro-91 ? reverse-engineered prompt

Build me a browser based monthly timesheet app in German for tracking work hours, breaks, and notes.

It should show all days of the month, highlight weekends, and automatically calculate daily hours, total hours, and pay with a 43 hour threshold where everything above that gets a lower rate. Let users enter times easily on mobile too, like 9 15, 9 15, 7:30 15, or just 915, and make sure shifts over midnight and breaks are handled correctly.

I want everything saved only in the browser for each device, with month switching, search across past timesheets, and a backup import and export so a user can move their data to a new device without overwriting existing entries. Add Excel export, a clean print friendly PDF export, and make the page fit nicely on A4. Keep it privacy friendly, with no login and no shared company data filled in.

If you need current docs for the libraries, look them up online first.