port graphiql_router_screens from core plugin

[josephfusco]

User Story

As a WordPress developer, I would like to be able to actions/filter various parts of the GraphiQL IDE to provide customized functionality.

Acceptance Criteria

• new action/filter names is prefixed with wpgraphqlide_
• existing functionality of action/filter is honored
• ported action/filter is documented

Reference

• Core plugin
• Existing documentation

Note that this is unlikely to be ported over considering the latest drawer GUI.

Confirm if that is still the case, even for a dedicated editor page.

[jasonbahl]

We're not migrating this JavaScript action from the legacy IDE as the concept of "Screens" isn't coming over in the same way.

In the legacy IDE we had "Screens" such as "GraphiQL" and "Help":

But in the new IDE we're using "Activity Panels" to accomplish the same things.

There may or may not be similar doAction calls added to support the rendering of the Activity Panels but not a 1:1 migration.

[josephfusco]

Closing in favor of #109