Save recipes from Android’s share menu

Implementation — 29 October 2026: implemented, pending release. Android shares open the URL import sheet with the link filled in and a choice of writable recipe book. Nothing is fetched or saved until Import is chosen. Cold and warm launches were checked with a freshly built Android debug APK on an emulator. This requires a native app update and is not released. Publishing a desktop browser clipper / capture from every browser is explicitly not planned in this resolution.