Function export_content 

pub fn export_content(
    capture_dir: &Path,
    id: &str,
    output: &Path,
    allow_content_export: bool,
) -> Result<(), ExportError>

Export the ephemeral capture bundle for id into a fresh private file. Fail-closed: requires allow_content_export, an existing unexpired bundle, and re-redacts before writing. Consumes (deletes) the bundle.