feat: menu & API Informasi Sekolah untuk aplikasi wali

- Tabel school_informations (judul, isi, kategori, tanggal kegiatan, publish)
- Menu admin 'Informasi Sekolah' (CRUD + permission manage-school-info)
- API wali: GET /parent/school-informations (hanya yang dipublikasikan)
- 2 data contoh: Jadwal UTS & Class Meet
- Test suite tetap hijau (39 test)

app/Models/SchoolInformation.php

@@ -0,0 +1,28 @@
+<?php
+
+namespace App\Models;
+
+use Illuminate\Database\Eloquent\Model;
+
+class SchoolInformation extends Model
+{
+    protected $table = 'school_informations';
+
+    protected $fillable = [
+        'title', 'content', 'category', 'event_date', 'is_published', 'published_at', 'created_by',
+    ];
+
+    protected function casts(): array
+    {
+        return [
+            'event_date' => 'date',
+            'is_published' => 'boolean',
+            'published_at' => 'datetime',
+        ];
+    }
+
+    public function creator()
+    {
+        return $this->belongsTo(User::class, 'created_by');
+    }
+}