Three problems were blocking the round-trip. Each fixed.
* MediaBridge.importFromURL went through the file-import service but not the Zustand store, so the media bin stayed empty. mam-bridge now calls window.__projectStore.getState().importMedia(file) which is what the actual UI uses. project-store.ts exposes useProjectStore on window for that hook.
* rustfs serves the proxy with content-type application/octet-stream; the editor rejects with DECODE_ERROR on that mime. Bridge now forces video/mp4 (or audio/wav, video/webm, etc.) based on the asset filename.
* The Recover Your Work modal and the Welcome tour blocked editor initialization. Bridge now auto-clicks Start Fresh and Skip Tour (alongside the format chooser), and waits 1.5s of project-id stability before calling importMedia so it does not get clobbered by the project-replacement cycle. One-shot guard prevents duplicate imports.
Zac
e390f0efab