The Sign-in links navigate with a full page load (they mount in a
separate React root without Router context), which wipes the in-memory
Zustand workspace. New utils/workspaceDraft stashes the whole workspace
(reusing the lossless .vlx serialisation) to sessionStorage before that
navigation and restores it once when the editor remounts after login —
so a user who was building a circuit and signs in lands back on their
work instead of the empty starter board.
Strictly scoped to the login round-trip by a one-shot restore flag (not
a general autosave), and skipped when a named project is already loaded
so it never clobbers one. EditorPage calls restoreStashedWorkspace() on
mount; the pro overlay's auth links call stashWorkspaceForAuth() before
navigating.
David Montero Crespo