Function resolve_file_in_base 

pub async fn resolve_file_in_base(base: &Path, path: &str) -> Option<PathBuf>

Resolves a file path within a base directory with path-traversal protection.

Canonicalizes both the file path and the base directory, then verifies that the canonical file path starts with the canonical base directory.

Arguments

• &Path - The base directory to resolve within.
• &str - The relative path to the file.

Returns

• Option<PathBuf> - The resolved file path if valid, None otherwise.