feat: [menu] menu_favorites 테이블 마이그레이션 추가

- tenant_id, user_id, menu_id, sort_order 컬럼
- unique 제약: (tenant_id, user_id, menu_id)
- FK cascade delete: users, menus

database/migrations/2026_03_06_143037_create_menu_favorites_table.php

@@ -0,0 +1,37 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    /**
+     * Run the migrations.
+     */
+    public function up(): void
+    {
+        Schema::create('menu_favorites', function (Blueprint $table) {
+            $table->id();
+            $table->unsignedBigInteger('tenant_id')->comment('테넌트 ID');
+            $table->unsignedBigInteger('user_id')->comment('사용자 ID');
+            $table->unsignedBigInteger('menu_id')->comment('메뉴 ID');
+            $table->integer('sort_order')->default(0)->comment('표시 순서');
+            $table->timestamps();
+
+            $table->unique(['tenant_id', 'user_id', 'menu_id']);
+            $table->index(['tenant_id', 'user_id', 'sort_order']);
+
+            $table->foreign('user_id')->references('id')->on('users')->cascadeOnDelete();
+            $table->foreign('menu_id')->references('id')->on('menus')->cascadeOnDelete();
+        });
+    }
+
+    /**
+     * Reverse the migrations.
+     */
+    public function down(): void
+    {
+        Schema::dropIfExists('menu_favorites');
+    }
+};