Event identifiers for anonymizations

database/migrations/2026_02_14_140010_create_events.php

@@ -42,6 +42,7 @@ return new class extends Migration {
             $table->foreignId('cost_unit_id')->nullable()->constrained('cost_units', 'id')->restrictOnDelete()->cascadeOnUpdate();
 
             $table->string('name');
+            $table->string('identifier');
             $table->string('location');
             $table->string('postal_code');
             $table->string('email');