Add isInvitation to BilletOrder, orga details in PDF footer, rename Sortie libre

- Add isInvitation (nullable bool) to BilletOrder: null=no badge, true=invitation
- PDF footer: add SIRET, email, phone of organizer
- PDF: show invitation badge based on ticket.isInvitation instead of design
- Rename "Sortie libre" to "Sortie - Entree illimitee"

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

migrations/Version20260321220000.php

@@ -0,0 +1,26 @@
+<?php
+
+declare(strict_types=1);
+
+namespace DoctrineMigrations;
+
+use Doctrine\DBAL\Schema\Schema;
+use Doctrine\Migrations\AbstractMigration;
+
+final class Version20260321220000 extends AbstractMigration
+{
+    public function getDescription(): string
+    {
+        return 'Add is_invitation to billet_order';
+    }
+
+    public function up(Schema $schema): void
+    {
+        $this->addSql('ALTER TABLE billet_order ADD COLUMN IF NOT EXISTS is_invitation BOOLEAN DEFAULT NULL');
+    }
+
+    public function down(Schema $schema): void
+    {
+        $this->addSql('ALTER TABLE billet_order DROP COLUMN IF EXISTS is_invitation');
+    }
+}