add set persistence

backend/app/Providers/AppServiceProvider.php

@@ -16,6 +16,8 @@ use App\Email\Emailer;
 use App\Email\EmailFactory;
 use App\Email\LaravelEmailer;
 use App\Email\LaravelEmailFactory;
+use App\Set\EloquentSetRepository;
+use App\Set\SetRepository;
 use App\User\EloquentUserRepository;
 use App\User\UserRepository;
 use Carbon\CarbonImmutable;
@@ -45,6 +47,10 @@ class AppServiceProvider extends ServiceProvider
         );
         $this->app->bind(Emailer::class, LaravelEmailer::class);
         $this->app->bind(EmailFactory::class, LaravelEmailFactory::class);
+        $this->app->bind(
+            SetRepository::class,
+            EloquentSetRepository::class,
+        );
         $this->app->bind(PasswordHasher::class, BcryptPasswordHasher::class);
         $this->app->bind(TokenGenerator::class, RandomTokenGenerator::class);
         $this->app->bind(Clock::class, SystemClock::class);

backend/app/Set/CreateSetDto.php

@@ -0,0 +1,13 @@
+<?php
+
+namespace App\Set;
+
+use App\User\User;
+
+final readonly class CreateSetDto
+{
+    public function __construct(
+        public string $name,
+        public User $creator,
+    ) {}
+}

backend/app/Set/EloquentSetRepository.php

@@ -0,0 +1,56 @@
+<?php
+
+namespace App\Set;
+
+use App\User\UserRepository;
+use RuntimeException;
+
+class EloquentSetRepository implements SetRepository
+{
+    public function __construct(
+        private UserRepository $userRepository,
+    ) {}
+
+    public function create(CreateSetDto $dto): Set
+    {
+        $model = SetModel::create([
+            'name' => $dto->name,
+            'creator_id' => $dto->creator->getId(),
+        ]);
+
+        return new Set(
+            id: $model->id,
+            name: $model->name,
+            creator: $dto->creator,
+        );
+    }
+
+    public function all(): array
+    {
+        $models = SetModel::query()
+            ->orderBy('name')
+            ->orderBy('id')
+            ->get();
+        $sets = [];
+
+        foreach ($models as $model) {
+            $sets[] = $this->toDomain($model);
+        }
+
+        return $sets;
+    }
+
+    private function toDomain(SetModel $model): Set
+    {
+        $creator = $this->userRepository->find($model->creator_id);
+        if ($creator === null) {
+            throw new RuntimeException('set creator not found');
+        }
+
+        return new Set(
+            id: $model->id,
+            name: $model->name,
+            creator: $creator,
+        );
+    }
+}

backend/app/Set/Set.php

@@ -0,0 +1,29 @@
+<?php
+
+namespace App\Set;
+
+use App\User\User;
+
+final readonly class Set
+{
+    public function __construct(
+        private int $id,
+        private string $name,
+        private User $creator,
+    ) {}
+
+    public function getId(): int
+    {
+        return $this->id;
+    }
+
+    public function getName(): string
+    {
+        return $this->name;
+    }
+
+    public function getCreator(): User
+    {
+        return $this->creator;
+    }
+}

backend/app/Set/SetModel.php

@@ -0,0 +1,26 @@
+<?php
+
+namespace App\Set;
+
+use Illuminate\Database\Eloquent\Attributes\Fillable;
+use Illuminate\Database\Eloquent\Builder;
+use Illuminate\Database\Eloquent\Model;
+
+/**
+ * @property int $id
+ * @property string $name
+ * @property int $creator_id
+ *
+ * @method static Builder<static>|SetModel newModelQuery()
+ * @method static Builder<static>|SetModel newQuery()
+ * @method static Builder<static>|SetModel query()
+ *
+ * @mixin \Eloquent
+ */
+#[Fillable(['name', 'creator_id'])]
+class SetModel extends Model
+{
+    protected $table = 'sets';
+
+    public $timestamps = false;
+}

backend/app/Set/SetRepository.php

@@ -0,0 +1,13 @@
+<?php
+
+namespace App\Set;
+
+interface SetRepository
+{
+    public function create(CreateSetDto $dto): Set;
+
+    /**
+     * @return list<Set>
+     */
+    public function all(): array;
+}

backend/database/migrations/2026_08_03_000000_create_sets_table.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
+    {
+        Schema::create('sets', function (Blueprint $table): void {
+            $table->id();
+            $table->string('name')->unique();
+            $table->foreignId('creator_id')
+                ->constrained('users')
+                ->restrictOnDelete();
+        });
+    }
+
+    public function down(): void
+    {
+        Schema::dropIfExists('sets');
+    }
+};