fix: correctly calculate due dates for contract and invoice uploads

src/Entity/Disposition.php

@@ -233,6 +233,14 @@ class Disposition implements BlameableEntityInterface, TimestampableEntityInterf
         $dueDateFrom = $this->getCreatedAt()->modify(sprintf('+%d days', $deadlineDays));
         $dueDateTo = $assignmentPeriod->end->modify('-1 day');
 
+        // A short-notice assignment can end before the normal $deadlineDays window would even
+        // start. Left uncapped, dueDateFrom >= dueDateTo makes isStarted() and isEnded() equal
+        // at every instant below, so the flag would never light up; treat the contract as due
+        // right away instead.
+        if ($dueDateFrom >= $dueDateTo) {
+            $dueDateFrom = $this->getCreatedAt();
+        }
+
         $period = CarbonPeriodImmutable::create($dueDateFrom, $dueDateTo);
 
         // isStarted() alone stays true once the period has begun, so the dashboard kept