To-Do cron task decay fixes (#12072)

* fix(tasks): improve some cron behaviors
Fixes #6488
Fixes #8590

* add test

Co-authored-by: Matteo Pagliazzi <matteopagliazzi@gmail.com>

website/common/script/ops/scoreTask.js

@@ -43,7 +43,7 @@ function _calculateDelta (task, direction, cron) {
     }
 
     // If To-Do, point-match the TD per checklist item completed
-    if (task.type === 'todo') {
+    if (task.type === 'todo' && !cron) {
       nextDelta *= 1 + reduce(task.checklist, (m, i) => m + (i.completed ? 1 : 0), 0);
     }
   }