v4.4.1

Fixed

• download_dir was missing from the generate_image and generate_video tool schemas — the 4.3.0 insertion matched only single-line filename schema declarations, and these two tools (the highest-traffic ones) declare filename as a multi-line block, so agents couldn't discover the parameter. The handlers already honored download_dir (verified live), so this is a discoverability fix, not a behavior change; both schemas now advertise it like the other 21 file-writing tools.