fix: add directory validation in getIds() before scandir()

Previously, scandir() was called in HarFileRepository::getIds() without
checking if the directory exists, which could trigger PHP warnings.

This adds a validation check using is_dir() before calling scandir(),
returning an empty array if the directory doesn't exist. This complements
the earlier fix in loadJson() and ensures consistent error handling.

Also adds a test case to verify the behavior when getIds() is called
with a non-existent directory path.

Author: claude

src/Repository/HarFileRepository.php

@@ -47,6 +47,10 @@ public function loadMultiple(array $ids = []): \Generator
 
     public function getIds(): array
     {
+        if (!is_dir($this->repositoryPath)) {
+            return [];
+        }
+
         $hars = scandir($this->repositoryPath);
         if (!$hars) {
             return [];

tests/src/Unit/Repository/HarFileRepositoryTest.php

@@ -83,4 +83,12 @@ public function testLoadJsonThrowsExceptionForInvalidFile()
         $this->expectException(\RuntimeException::class);
         $this->repository->loadJson('non-existent-file.har');
     }
+
+    public function testGetIdsReturnsEmptyArrayForNonExistentDirectory()
+    {
+        $repository = new HarFileRepository('/path/to/non-existent-directory');
+        $ids = $repository->getIds();
+        $this->assertIsArray($ids);
+        $this->assertEmpty($ids);
+    }
 }