forked from 1b-agent/opencadstudio-upstream
On the web, Save and Save As now open the in-app Save dialog (filename + format) like the desktop, and the unsaved-changes prompt's Save routes through it too — instead of an immediate rfd download. Confirm serializes to bytes and downloads directly via a Blob + hidden `<a download>` click (a user gesture), so there is no intermediate "click to download" link. Replaces the rfd-based download_web / WebSaveResult round-trip with a synchronous sys::download_bytes. Native save is unchanged. Native + web build; 75 tests pass. Co-Authored-By: Claude Opus 4.8 <[email protected]>