feat(domains): add per-domain noindex support

Flagged domains are served with X-Robots-Tag: noindex, nofollow via
Traefik and Caddy routing labels, so an auto-generated technical domain
can be excluded from indexing while the production domain on the same
resource stays indexable.

database/migrations/2026_07_12_090000_add_noindex_domains_to_applications_and_service_applications.php

@@ -0,0 +1,30 @@
+<?php
+
+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('applications', function (Blueprint $table) {
+            $table->json('noindex_domains')->nullable()->after('fqdn');
+        });
+
+        Schema::table('service_applications', function (Blueprint $table) {
+            $table->json('noindex_domains')->nullable()->after('fqdn');
+        });
+    }
+
+    public function down(): void
+    {
+        Schema::table('applications', function (Blueprint $table) {
+            $table->dropColumn('noindex_domains');
+        });
+
+        Schema::table('service_applications', function (Blueprint $table) {
+            $table->dropColumn('noindex_domains');
+        });
+    }
+};