feat(registry): add configurable docker registry url (#9017)

database/migrations/2026_03_17_073223_add_docker_registry_url_to_instance_settings.php

@@ -0,0 +1,25 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    /**
+     * Run the migrations.
+     */
+    public function up(): void
+    {
+        Schema::table('instance_settings', function (Blueprint $table) {
+            $table->string('docker_registry_url')->default('docker.io')->after('is_auto_update_enabled');
+        });
+    }
+
+    public function down(): void
+    {
+        Schema::table('instance_settings', function (Blueprint $table) {
+            $table->dropColumn('docker_registry_url');
+        });
+    }
+};