test: probe the Codecov setup with uncovered source

src/CoverageProbe.php

@@ -0,0 +1,64 @@
+<?php declare(strict_types=1);
+/*
+ * (c) shopware AG <info@shopware.com>
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Swag\MigrationMagento;
+
+use Shopware\Core\Framework\Log\Package;
+
+/**
+ * @internal Probe for the Codecov setup — DO NOT MERGE.
+ */
+#[Package('fundamentals@after-sales')]
+class CoverageProbe
+{
+    public function classify(int $value): string
+    {
+        if ($value < 0) {
+            return 'negative';
+        }
+
+        if ($value === 0) {
+            return 'zero';
+        }
+
+        if ($value < 10) {
+            return 'small';
+        }
+
+        if ($value < 100) {
+            return 'medium';
+        }
+
+        return 'large';
+    }
+
+    /**
+     * @param list<int> $values
+     *
+     * @return list<string>
+     */
+    public function classifyAll(array $values): array
+    {
+        $result = [];
+        foreach ($values as $value) {
+            $result[] = $this->classify($value);
+        }
+
+        return $result;
+    }
+
+    public function describe(int $value): string
+    {
+        $label = $this->classify($value);
+
+        if ($label === 'zero') {
+            return 'the value is zero';
+        }
+
+        return \sprintf('the value is %s (%d)', $label, $value);
+    }
+}