Config file decryption/encryption support

Adds support for FH6 encrypted config files

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Config file (.ini) support

• Decrypt & re-encrypt FH6 encrypted config files. Drop a file like
  media\Physics\PhysicsSettings.ini and the tool now detects it, decrypts it to plain editable
  text, and re-encrypts your edits back into a loadable file.
• Auto-detected. Encrypted .ini / .cfg / .config files are recognized on drop and routed
  to the config path.

Workflow: drop the encrypted .ini → Decrypt → edit the text → Re-Encrypt (pick the
original encrypted file when asked) → close FH6, copy the result back in.