Detail of webapp production setup

Adding the following section to the infrastructure documentation:

Detail of webapp production setup

The ELB balances the load between 8 webapp EC2 instances. Each webapp instance runs:

• 2 web express servers started from the server/web.js
• 2 API express servers started from server/api.js

And users Nginx as a reverse proxy to route the incoming traffic based on the request path.

graph LR
A((User)) -- "HTTPS (443)" --> B[ELB]
B -- "HTTP (80)" --> C[Nginx]
subgraph "EC2 (webapp)"
C -- "/" --> D["web webapp (server/web.js)"]
C -- "/api{_staging}/*" --> E["api webapp (server/api.js)"]
end