chore: update docs for new ucanto integration

[yusefnapora]

This updates the markdown docs based on the changes in #119.

I think I got everything, but @alanshaw should probably take a look :)

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@w3ui/example-solid-file-upload	Configuration
@w3ui/example-solid-sign-up-in	Configuration
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@w3ui/example-vue-uploads-list	Configuration

[alanshaw]

🥳 Awesome thank you!