Function path_to_safe_dirname 

pub fn path_to_safe_dirname(path: &str) -> String

Convert a remote path to a safe directory name.

Sanitizes path by:

• Removing leading ~ and /
• Replacing path separators and spaces with underscores
• Removing parent directory references (..) to prevent traversal attacks
• Removing current directory references (.)
• Appending a stable hash to prevent collisions (e.g., “foo/bar” vs “foo_bar”)