[Feature Request] Use server in expense sample

[lorensr]

Looks like Val was porting the expense sample from the go one: https://github.com/temporalio/samples-go/tree/main/expense

Currently, the server code isn't used—we just start and signal the Workflow from the execute scripts directly. Server:

https://github.com/temporalio/samples-typescript/blob/main/expense/src/server/index.ts

[lorensr]

Nevermind, the activities use the server! I'll update the README. I was imagining the user on a website clicking a button that hit the server that sent the signal.