Add timing data to browser fetch

[carbonrobot]

Adds timing data to browser fetch calls via @envyjs/web

Browsers prevent full timing data from being accessed from cross-origin requests unless the server responds with the Timing-Allow-Origin header

Added CORS headers to the Apollo example, so we can see the full dataset. When data is blocked, the UX shows a link to the documentation on how to enable CORS for timing data

With CORS allowed

Without CORS allowed

[changeset-bot]

🦋 Changeset detected

Latest commit: 4a12065

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 2 packages

Name	Type
@envyjs/webui	Minor
@envyjs/web	Minor

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[exogen]

Is it possible to detect when timing data was allowed and when it wasn't? (I assume we could check for zeros but wonder if there's a more bulletproof way.) It would be nice in the design if (above/below the timing graph) there was a little infobox describing why full data isn't available and how to potentially enable it.

[carbonrobot]

@exogen agreed. Since the timing data is essentially useless when its blocked, maybe I'll add a block in the UI that describes the steps to enable it