feat: implement product and attachment management service with supporting migrations and API controllers

database/migrations/2026_06_29_150840_create_productos_attachments_table.php

@@ -0,0 +1,35 @@
+<?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('productos_attachments', function (Blueprint $table) {
+            $table->id();
+            $table->foreignId('producto_id')
+                ->constrained('productos')
+                ->cascadeOnDelete();
+            $table->foreignId('attachment_id')
+                ->constrained('attachments')
+                ->cascadeOnDelete();
+            $table->timestamps();
+
+            $table->unique(['producto_id', 'attachment_id']);
+        });
+    }
+
+    /**
+     * Reverse the migrations.
+     */
+    public function down(): void
+    {
+        Schema::dropIfExists('productos_attachments');
+    }
+};