Server Cleanup & Maintenance Tools

[rdp77]

Add a Cleanup & Maintenance section to the server panel for safely cleaning unnecessary files and logs.

For Ubuntu servers, provide common cleanup actions such as:

Clean system logs and journal logs
Clean APT cache and unused packages
Remove old temporary files
Clean old compressed logs
Show estimated disk space before and after cleanup

The cleanup process should use safe, predefined commands based on the server OS, with each operation clearly explained before execution.

Example Ubuntu cleanup routines can be based on: https://gist.github.com/Iman/8c4605b2b3ce8226b08a