Add registry availability check

src/StaticPHP/Doctor/Item/RegistryCheck.php

@@ -0,0 +1,23 @@
+<?php
+
+declare(strict_types=1);
+
+namespace StaticPHP\Doctor\Item;
+
+use StaticPHP\Attribute\Doctor\CheckItem;
+use StaticPHP\Doctor\CheckResult;
+use StaticPHP\Registry\Registry;
+use ZM\Logger\ConsoleColor;
+
+class RegistryCheck
+{
+    #[CheckItem('if at least one registry is configured', level: 99999)]
+    public function checkRegistry(): ?CheckResult
+    {
+        $regs = Registry::getLoadedRegistries();
+        if (count($regs) > 0) {
+            return CheckResult::ok(implode(',', array_map(fn ($x) => ConsoleColor::green($x), $regs)));
+        }
+        return CheckResult::fail('No registry configured');
+    }
+}