FileRise: Insecure default cryptographic key fallback in manual installs

FileRise is a self-hosted web-based file manager with multi-file upload, editing, and batch operations. From 3.9.0 until 3.22.0, pristine manual FileRise installations without PERSISTENT_TOKENS_KEY or metadata/persistent_tokens.key can activate a published legacy compatibility key. If an attacker separately obtains ciphertext-bearing account or configuration files, the known fallback key can enable decryption of TOTP secrets or credentials. Docker installations already generated a unique persistent key, and existing installations are not automatically rotated because doing so could make encrypted state unreadable. This issue is fixed in version 3.22.0.