Copy `taskpaper-lite` to a custom variant
Sync date formats from `taskpaper` template

The default `taskpaper-lite` template uses @yyyy-mm-dd instead of @done(yyyy-mm-dd) and a modified "dateFormat": "%Y-%m-%d-%a"
This customized variant uses the same date format and completion tag syntax as the main `taskpaper` template for consistency.
Use new custom template variant: `taskpaper-lite-done`
Merge branch 'feature/custom-taskpaper-lite' into develop

* feature/custom-taskpaper-lite:
  Use new custom template variant: `taskpaper-lite-done`
  Sync date formats from `taskpaper` template
  Copy `taskpaper-lite` to a custom variant