Display directives in schema and popup tooltips.

[leniency]

Product

Nitro

Is your feature request related to a problem?

Directives are discoverable in Nitro when viewing the SDL but not elsewhere. We use several custom directives for security checks and it would be nice to make the requirements more discoverable.

The solution you'd like

It would be very handy to make the directives, especially custom directives, more visible throughout. For example, these two locations would be quite useful:

1. In the query editor when hovering an operation - list directives below the operation description.
   

2. Under the schema reference - list the directives somewhere alongside the variables: