Starter code for the gradual explanation on how to create a ticket booking system to solve for the double booking system and provide a good UX for clients when booking a ticket and avoid conflicts in a high contention enviroment.
Two users click "Book" on seat A1 at the same instant. Only one should win.
User A ──► read seat A1 → "free" ──► write booking ──► success
User B ──► read seat A1 → "free" ──► write booking ──► ???Without any protection, both succeed. Now two people show up for the same seat.
