How can the script be modified to ensure proper handling and deletion of uploaded files?

To ensure proper handling and deletion of uploaded files, the script should check for file existence before attempting to delete it. This can be done by using the `file_exists()` function in PHP. Additionally, it is important to set proper file permissions and sanitize user input to prevent any security vulnerabilities.

// Check if the file exists before deleting
if (file_exists($file_path)) {
    unlink($file_path);
    echo "File deleted successfully.";
} else {
    echo "File not found.";
}