[graphiql] show response headers in UI

[n1ru4l]

It would be great if there was a way to show the response headers in the GraphiQL UI. This would be great for use cases where you implement stuff like E-Tag and If-None-Match on top of GraphQL.

[acao]

this has been requested many times! this was part of orta's design as well

I propose we implement this as a plugin and an extension of the plugin system, similarly to

#2795

[acao]

I was also hoping this panel could have plugin tabs for operation tracing as well, and other diagnostics/metadata potentially

[klippx]

Petition to be able to extend this with e.g. duration (as measured from client) in case this is not available in headers.

In Apollo Studio we get this, and as you an see it is not part of headers

Response area, selecting response (default):

Response area, selecting response headers:

[acao]

I have plans to extend the plugin system to support this this year! However, first we need to convert the graphiql state management away from context