Add A2UI-Composer

[maxkorp]

Adds an app called A2UI-Composer which generates a2ui widgets. Available hosted at a2ui-editor.ag-ui.com.

Note the hosted ui is slightly out of sync since it is deploying from a different repository, will clean up once this is all live as discussed with @zeroasterisk

demo.mp4

[google-cla]

Thanks for your pull request! It looks like this may be your first contribution to a Google open source project. Before we can look at your pull request, you'll need to sign a Contributor License Agreement (CLA).

View this failed invocation of the CLA check for more information.

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[maxkorp]

I've signed the CLA and my github info is accurate as I can see on https://cla.developers.google.com, but still showing up as not signed for some reason

[zeroasterisk]

I've signed the CLA and my github info is accurate as I can see on https://cla.developers.google.com, but still showing up as not signed for some reason

Hey @maxkorp , please make sure both you and @mme have done the CLA and that it's for the email address in the commits. There's a button in the error to rescan or we can keep poking it to rescan. This CLA is a requirement for the merge.

Otherwise, thanks!! I'm excited to see it.

[ataibarkai]

@zeroasterisk Markus (@mme) also signed the CLA - looks like we're good to go except for a human PR approval.

[ava-cassiopeia]

This is a big PR, so it will take me awhile before I can review it fully.

That being said, I do see some parts of this PR that could potentially be broken up, if you're willing to do so. If you split up this PR, that makes reviewing all this code considerably easier.

For example, I see some copilot-related code, some changes to the a2ui renderer itself, some changes to core libraries, etc.

[maxkorp]

There are some pre-publishing packages included here that can be ripped out, so this becomes much smaller, I'll get that updated today

[maxkorp]

Hrm, unsure why this closed when I force pushed, but I'll open a new one?

[maxkorp]

@zeroasterisk @ava-cassiopeia had to remake the PR: #365

CC @ataibarkai @mme