<!-- CURSOR_SUMMARY -->
> [!NOTE]
> Introduces real-time web search in chat with streaming results and a
richer UI.
> 
> - Adds `web_search` tool (`tools/web_search.ts`) with zod schema,
consent prompt, SSE parsing, and streaming via
`onXmlStream`/`onXmlComplete` (requires Dyad Pro API key; respects
`DYAD_ENGINE_URL`)
> - Registers tool in `TOOL_DEFINITIONS`
> - Updates markdown parser to pass `query` and `state` into
`dyad-web-search`
> - Enhances `DyadWebSearch` component: expandable/collapsible card,
loading spinner while `pending`, keyboard/ARIA support, and displays
query preview + results
> 
> <sup>Written by [Cursor
Bugbot](https://cursor.com/dashboard?tab=bugbot) for commit
53c9c7b65eb8dee07d8320837b39d72bf5b42b92. This will update automatically
on new commits. Configure
[here](https://cursor.com/dashboard?tab=bugbot).</sup>
<!-- /CURSOR_SUMMARY -->

<!-- This is an auto-generated description by cubic. -->
---
## Summary by cubic
Adds web search to chat with live streaming results from Dyad Engine.
The Web Search card shows the query, a loading state, and
expand/collapse for details.

- **New Features**
- New web_search tool that streams SSE results and writes partial
updates via onXmlStream, final via onXmlComplete.
  - Registered tool in TOOL_DEFINITIONS with consent and zod schema.
- DyadWebSearch UI: accepts query/state, shows spinner when pending, and
toggles preview/details.
  - Markdown parser now passes query and state to DyadWebSearch.

- **Migration**
- Requires Dyad Pro API key in settings (providerSettings.auto.apiKey).
- Optional: set DYAD_ENGINE_URL; defaults to https://engine.dyad.sh/v1.

<sup>Written for commit 53c9c7b65eb8dee07d8320837b39d72bf5b42b92.
Summary will update on new commits.</sup>

<!-- End of auto-generated description by cubic. -->