PicMason HEIC/HEIF decoding third-party notices

The browser-only HEIC/HEIF still-image decoder uses:

1. @su-engineering/heic 0.2.0, Copyright (c) 2026 SU Engineering, MIT License.
   Source: https://github.com/su-engineering/heic-web/tree/master
   License: /licenses/su-engineering-heic-MIT.txt

2. libheif-js 1.23.5 and its bundled libheif codec build, LGPL-3.0.
   Source: https://github.com/catdad-experiments/libheif-js/tree/v1.23.5
   License: /licenses/libheif-js-LGPL-3.0.txt
   Upstream codec notices and license texts: /licenses/libheif-codec-notices.txt

The software fallback is loaded only when a browser cannot decode the selected
HEIC photo natively or through WebCodecs. PicMason does not send the selected
photo to a server to decode it.