docs: full migration of docs/ to fern format in fern/ (#6050)

Signed-off-by: Dan Gil <dagil@nvidia.com>
Co-authored-by: Cursor <cursoragent@cursor.com>

fern/pages/kubernetes/chrek/standalone.md

-# ChReK Standalone Usage Guide
+---
+# SPDX-FileCopyrightText: Copyright (c) 2025-2026 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+# SPDX-License-Identifier: Apache-2.0
+---
 
 > ⚠️ **Experimental Feature**: ChReK is currently in **beta/preview**. It requires privileged mode for restore operations, which may not be suitable for all production environments. Review the [security implications](#security-considerations) before deploying.