add dated assignment endpoint

backend/app/Schedule/AssignmentForDate.php

@@ -0,0 +1,27 @@
+<?php
+
+namespace App\Schedule;
+
+final readonly class AssignmentForDate
+{
+    public function __construct(
+        private int $scheduleId,
+        private string $setName,
+        private ScheduleAssignment $assignment,
+    ) {}
+
+    public function getScheduleId(): int
+    {
+        return $this->scheduleId;
+    }
+
+    public function getSetName(): string
+    {
+        return $this->setName;
+    }
+
+    public function getAssignment(): ScheduleAssignment
+    {
+        return $this->assignment;
+    }
+}