feat: entité Website liée à Customer avec UUID, type et state machine

Entity Website :
- customer (ManyToOne, CASCADE) : client propriétaire
- name : nom du site
- uuid : UUID v4 auto-généré (unique, 36 chars)
- type : vitrine | ecommerce
- state : created → install_progress → open → suspended → closed
- createdAt / updatedAt (auto sur setState)
- isOpen() : vérifie si state === open

WebsiteTest (5 tests, 20 assertions) :
- testConstructor : valeurs par défaut, uuid 36 chars, type vitrine
- testConstructorEcommerce : type ecommerce
- testSetters : name, type, updatedAt
- testState : transitions created→install_progress→open→suspended→closed
- testUuidUnique : 2 sites ont des uuid différents

Dépendance : symfony/uid ajouté pour Uuid::v4()
Migration : CREATE TABLE website avec FK customer, uuid unique

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

migrations/Version20260404190626.php

@@ -0,0 +1,35 @@
+<?php
+
+declare(strict_types=1);
+
+namespace DoctrineMigrations;
+
+use Doctrine\DBAL\Schema\Schema;
+use Doctrine\Migrations\AbstractMigration;
+
+/**
+ * Auto-generated Migration: Please modify to your needs!
+ */
+final class Version20260404190626 extends AbstractMigration
+{
+    public function getDescription(): string
+    {
+        return '';
+    }
+
+    public function up(Schema $schema): void
+    {
+        // this up() migration is auto-generated, please modify it to your needs
+        $this->addSql('CREATE TABLE website (id INT GENERATED BY DEFAULT AS IDENTITY NOT NULL, name VARCHAR(255) NOT NULL, uuid VARCHAR(36) NOT NULL, type VARCHAR(20) NOT NULL, state VARCHAR(20) NOT NULL, created_at TIMESTAMP(0) WITHOUT TIME ZONE NOT NULL, updated_at TIMESTAMP(0) WITHOUT TIME ZONE DEFAULT NULL, customer_id INT NOT NULL, PRIMARY KEY (id))');
+        $this->addSql('CREATE UNIQUE INDEX UNIQ_476F5DE7D17F50A6 ON website (uuid)');
+        $this->addSql('CREATE INDEX IDX_476F5DE79395C3F3 ON website (customer_id)');
+        $this->addSql('ALTER TABLE website ADD CONSTRAINT FK_476F5DE79395C3F3 FOREIGN KEY (customer_id) REFERENCES customer (id) ON DELETE CASCADE NOT DEFERRABLE');
+    }
+
+    public function down(Schema $schema): void
+    {
+        // this down() migration is auto-generated, please modify it to your needs
+        $this->addSql('ALTER TABLE website DROP CONSTRAINT FK_476F5DE79395C3F3');
+        $this->addSql('DROP TABLE website');
+    }
+}