docs(ecosystem): add svelte-a2ui (Svelte 5 community renderer)

[ChaliceForAuri]

Adds svelte-a2ui — a Svelte 5 renderer — to the Community Renderers table, filling the roadmap's "Svelte/Kit — Community interest" slot.

What it is: a runes-native A2UI renderer targeting the v1.0 Candidate spec (property names shared with v0.9). Full Basic Catalog: all 18 components, the complete 59-name Icon enum + {svgPath}, all 14 built-in functions, checks validation, collection templates. The test suite (83 protocol tests on node --test, 19 browser tests on headless Chromium) includes a replay of the spec's own contact_form_example fixture.

Architecture: pure-reducer protocol core with structural sharing, held in $state.raw — unchanged components keep referential identity and skip re-rendering. The threat model assumes a hostile agent: catalog allowlist, unconditional on*/function stripping, prototype-pollution refusal, escape-then-markup text rendering, bounded recursion, callableFrom enforcement.

Transports: HTTP JSONL/SSE, the A2A extension binding (application/a2ui+json DataParts, metadata lifted to the A2A message per the extension spec), and AG-UI activities (including a2ui-surface from @ag-ui/a2ui-middleware). a2uiRendererCapabilities is advertised on every outbound message.

Listing criteria:

• ✅ Published source, Apache-2.0: https://github.com/ChaliceForAuri/a2ui-svelte
• ✅ Spec version stated: v1.0 Candidate (v0.9-compatible component names; v0.8 not supported)
• ✅ Basic component coverage: all 18
• ✅ README with install + minimal usage: https://www.npmjs.com/package/svelte-a2ui
• ✅ Actively maintained; CI runs the full suite on every push
• Live demo (progressive streaming, validation gating, action round-trip): https://chaliceforauri.github.io/a2ui-svelte/

🤖 Generated with Claude Code

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[gemini-code-assist]

Code Review

This pull request adds the ChaliceForAuri/a2ui-svelte (svelte-a2ui) Svelte 5 renderer to the community renderers table and includes a detailed description of its features and capabilities. The review feedback suggests improving the description's readability by fixing a sentence fragment, formatting {svgPath} as code, and clarifying that the client determines a function's execution boundary at runtime based on the active catalog definition.

[ChaliceForAuri]

@googlebot I signed it!

[ChaliceForAuri]

@googlebot I signed it!

[ChaliceForAuri]

@googlebot I signed it!

[polina-c]

I checked the demo - when i click 'Book table' nothing happens in UI.

Should new UI be rendered as result of interaction?

[ChaliceForAuri]

Great catch, thank you — and no, that wasn't intended behaviour, it was a gap in the demo.

You're right that new UI should be the result: in A2UI an action is a request, not a form submission, and the agent answers with more UI. My mock agent simply had nothing scripted to say back, so the action left the renderer (visible in the wire feed on the right) and then… silence.

Fixed and deployed. Booking now gets a reply: updateDataModel writes the booking details, then updateComponents re-points root at a confirmation surface — which is a much better demonstration of the model than what was there before, since "navigating to a new screen" turns out to be just more data. There's a Book another table button that replays the original stream.

Live at demo — the wire feed shows the full round trip now: the action going up (179 bytes, hand-picked context only), then the agent's reply coming back down.

Thanks for actually clicking through it.