Convert intervention tabs to singular list

[lgeorge-idm]

Summary

This is split from #202. The request is to see all interventions in a single table as opposed to a tabbed interface.

Suggested solution

• Use a dropdown to select the intervention type and then list the interventions in a tabular format
• Enables reusing existing code and requires minimal refactoring of the front end.

Additional context

• Changing to to as static table requires changing the entire eventing model, validation model, and rendering. First pass done here:

[cliffckerr]

Now that Covasim has been publicly released, let's take a step back and scope this out a little more carefully.