feat: add customer details fields to Purchase model and request, implement checkout process with cart clearing

database/migrations/2026_07_03_193000_adapt_compras_table.php

@@ -0,0 +1,31 @@
+<?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::table('compras', function (Blueprint $table) {
+            $table->string('dni')->nullable()->after('payment_method');
+            $table->string('telefono')->nullable()->after('dni');
+            $table->string('nombre_apellido')->nullable()->after('telefono');
+            $table->string('email')->nullable()->after('nombre_apellido');
+        });
+    }
+
+    /**
+     * Reverse the migrations.
+     */
+    public function down(): void
+    {
+        Schema::table('compras', function (Blueprint $table) {
+            $table->dropColumn(['dni', 'telefono', 'nombre_apellido', 'email']);
+        });
+    }
+};