LibCore: Add utility class for temporary files and directories

Core::TempFile is a RAII type that creates a temporary file or directory
on construction and deletes it on destruction.

Userland/Libraries/LibCore/TempFile.h

@@ -0,0 +1,37 @@
+/*
+ * Copyright (c) 2020-2021, the SerenityOS developers.
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <AK/Noncopyable.h>
+#include <AK/String.h>
+
+namespace Core {
+
+class TempFile {
+    AK_MAKE_NONCOPYABLE(TempFile);
+    AK_MAKE_NONMOVABLE(TempFile);
+
+public:
+    enum class Type {
+        File,
+        Directory
+    };
+
+    static NonnullOwnPtr<TempFile> create(Type = Type::File);
+    ~TempFile();
+
+    String path() const { return m_path; }
+
+private:
+    TempFile(Type);
+    static String create_temp(Type);
+
+    Type m_type { Type::File };
+    String m_path;
+};
+
+}