feat: notifikasi kehadiran ke wali per sesi (hadir/izin/sakit) saat sync e-jurnal + fix violation_id nullable

database/migrations/2026_08_06_000002_make_violation_id_nullable_in_violation_notifications.php

@@ -0,0 +1,24 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    public function up(): void
+    {
+        // violation_id boleh kosong untuk notifikasi non-pelanggaran
+        // (mis. notifikasi kehadiran & SP yang belum punya violation terkait).
+        Schema::table('violation_notifications', function (Blueprint $table) {
+            $table->foreignId('violation_id')->nullable()->change();
+        });
+    }
+
+    public function down(): void
+    {
+        Schema::table('violation_notifications', function (Blueprint $table) {
+            $table->foreignId('violation_id')->nullable(false)->change();
+        });
+    }
+};