One self-contained HTML file — no build, no server, no persistence. It is dressed as the working product: a patient list, a chart panel, an access log. Change who is signed in from the menu top right and watch the same records change shape underneath you.
The question: when a system says it keeps branches apart, is that real or just a screen that hides things? Every demo looks like it separates them. The doubt worth answering is whether the records are genuinely absent rather than merely off-screen, whether that still holds when somebody goes looking, and whether a permission that is supposed to end actually ends.
One prototype, built deep, rather than four competing directions — same reasoning as logistics/dispatch. There is nothing to choose between here; there is something to verify.
How to drive it. Pick a patient. Records you have no right to open are greyed rather than hidden, purely so you can try one — every refusal lands in the Access log tab with your name on it. The Demo drawer along the bottom holds five guided scenarios and an explanation of the three locks, and resets the clinic to day one.