Remove development server

[jonathanhliu21]

Is your feature request related to a problem? Please describe.
There isn't really a point to run in a development server because debug mode and automatic reloads don't work, and it is just slower than a production server.

Describe the solution you'd like
Only give the option to start a production server, either by the run_prod() method for backward compatibility, or a new run() method.

Describe alternatives you've considered
Keep the run_dev() method but make the production server default in the CLI.

Additional context
N/A