Changelog for workers-rs panic recovery

[guybedford]

Summary

Provides a technical changelog for the new workers-rs panic recovery functionality.

It's quite nice to go into the details here, but we could cut back on the content too if this is the wrong place for it.

Screenshots (optional)

Documentation checklist

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• The documentation style guide has been adhered to.
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[irvinebroque]

This is awesome and think it is good to get into this kind of detail here

[JohnDaWalka]

Thx

[danlapid]

LOVE IT

[mikenomitch]

@guybedford this feels more like part of a blog post or docs than a Changelog.

Instead of going into the details (at least initially), I'd make it much more to the point:

• Previously, when in workers-rs when a Rust panic occured, X would happen. This was bad because the Worker would then do Y.
• Now you can add the new setPanicHook functionality to handle these errors.

I thin we can and should go a little into the details after this, but I'd probably try to trim it down a bit from where its at.

Also, I see setPanicHook being imported from index.js. It's not clear to me where it actually comes from and how to implement. Is there a way to add some more color there?

EDIT: Brendan and Dan seemed more into including the details here than I was. 😄 - I'm okay keeping what we have as long as they don't interfere with immediately defining the problem and how we now solve it. So I'd push the wasm-bindgen bits down below, and explain "Wasm is a virtual machine" later too, and then I think its good.