Dutched: Split Expenses

Invite with a link. Friends who have Dutched land straight on the join screen with the group previewed; friends who don't get a page with the code to type after installing. Pick the day an expense happened, and let several people pay one expense. Every currency, and a group's currency can change later. Finished with a trip? Archive the group, or delete it once everyone is at zero. How people can pay you: turn off the apps you don't have, add your username, and settle-up links open on you. Add someone to the group from inside an expense, and add several people at once. Settle up your way: each group settles as "Fewest payments" or "Who owes whom", chosen when you create it. Settle up across groups in one go. Zelle can be recorded. A short first-run tour, and a nudge when a new version is out. Fixes: you stay signed in, "someone you already know" works, and sheets slide the way you'd expect. Both are recorded in docs/app-store-listing.md alongside the keywords and subtitle from 1.2. Once it's submitted and Apple releases it, tell me and I'll switch on the in-app update nudge.