feat: add date_of_birth field to persons across all layers

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

api/database/migrations/2026_04_10_500000_add_date_of_birth_to_persons_table.php

@@ -0,0 +1,24 @@
+<?php
+
+declare(strict_types=1);
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    public function up(): void
+    {
+        Schema::table('persons', function (Blueprint $table) {
+            $table->date('date_of_birth')->nullable()->after('last_name');
+        });
+    }
+
+    public function down(): void
+    {
+        Schema::table('persons', function (Blueprint $table) {
+            $table->dropColumn('date_of_birth');
+        });
+    }
+};