Improve multi-user experience for workflow application

[davidmezzetti]

Currently, the workflow application is cumbersome and really only designed for a single user. When multiple users interact with the application, there are a number of inefficiencies that should be fixed:

• Change st.cache to the active workflow vs the application. Workflows should be able to be shared between users and not reinitialized for each user.
• Store data and query as state variables
• Set keys on input fields to prevent duplicate key errors
• Use an st.form for workflow parameters, only submit once user clicks build vs on each field change.

The application is currently allowing 1 active workflow but that can easily be changed with the tradeoff of higher memory usage.