When Supabase is unreachable, employees were stuck on the login
screen with no way in, even though the app is fully usable offline
(orders, catalog, stock, etc. all live in localStorage already).
Adds a low-key link on the login screen that sets a local-only flag
and skips the auth gate entirely until a real cloud sign-in succeeds
(which clears the flag). Deliberately does not touch any cloud/session
state, so it can't trigger an automatic cloud pull that would overwrite
data created while working offline.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>