fix(client-web): scroll the web_search source card instead of collapsing

Replace the WebBlock search card's head/tail collapse and expand button
with a fixed-height scroll container that lists every source the tool
returned. The model-facing side is unchanged: the seam still caps sources
at searchMaxResults and the truncated indicator stays, so model-visible
and frontend-visible sources remain identical.

Remove CHAT_WEB_MAX_SOURCES and DEFAULT_WEB_MAX_SOURCES: with scroll, the
chat row and details panel show the same full list.

packages/client/ui-conversation/src/client/chat/ToolRow.tsx

@@ -30,7 +30,6 @@ import type { TranslateNS } from '@deepseek-ai/dsh-client-ui-slots'
 import { CHAT_DIFF_MAX_LINES, type DiffCardModel } from '../contract/diff-card-model.ts'
 import { CHAT_READ_MAX_LINES, type ReadCardModel } from '../contract/read-card-model.ts'
 import { CHAT_SEARCH_MAX_LINES, type SearchCardModel } from '../contract/search-card-model.ts'
-import { CHAT_WEB_MAX_SOURCES } from '../contract/web-card-model.ts'
 import { terminalBlockLabels, type TerminalCardModel } from '../contract/terminal-card-model.ts'
 import type { ToolRowState, ToolRowVariant } from '../contract/tool-call-model.ts'
 import { DisclosureRow } from './DisclosureRow.tsx'
@@ -276,7 +275,7 @@ export function ToolRow({
                     </>
                   )
                   : webBody !== null
-                    ? <WebBlock {...webBody} maxSources={CHAT_WEB_MAX_SOURCES} className={css.webBody} />
+                    ? <WebBlock {...webBody} className={css.webBody} />
                     : isThink
                       ? <div className={css.thinkBody}>{body}</div>
                       : (

packages/client/ui-conversation/src/client/contract/web-card-model.ts

@@ -15,16 +15,6 @@
 import type { WebBlockProps } from '@deepseek-ai/dsh-client-ui-primitives'
 import type { ToolCallBlock } from './tool-call-model.ts'
 
-/**
- * Sources the chat row's web body shows before collapsing the middle — half
- * the primitive's own default, which the details panel keeps. A chat row is a
- * summary surface inside the message flow: the flow must stay scannable across
- * many calls, while the details panel is the single-call reading surface. A
- * design constant of this UI's row geometry, not a deployment choice, so it is
- * fixed here rather than a plugin Config field.
- */
-export const CHAT_WEB_MAX_SOURCES = 8
-
 /**
  * Derive the web-card props for a tool call, or null when this call is not a
  * web card and belongs on the generic path.

packages/client/ui-conversation/src/client/skeleton/DetailsPanel.tsx

@@ -180,13 +180,12 @@ function OutputBody({ material, cwd, t }: { material: CallMaterial; cwd: string
     )
   }
   const web = webCardModel(material.block)
-  // Full source-list allowance here (the panel is the single-call reading
-  // surface); the chat rows cap it at CHAT_WEB_MAX_SOURCES. Below the card the
-  // panel also renders the flattened result content — the model-visible text
-  // the card does not carry verbatim (a web_fetch card shows only the URL and
-  // status, so its fetched body lives only here; a search card's answer and
-  // sources are structured, so the flattened form repeats them as the raw text
-  // the model saw).
+  // The card shows every source the tool returned (the same list the model saw),
+  // scrolling within its own capped height. Below the card the panel also renders
+  // the flattened result content — the model-visible text the card does not carry
+  // verbatim (a web_fetch card shows only the URL and status, so its fetched body
+  // lives only here; a search card's answer and sources are structured, so the
+  // flattened form repeats them as the raw text the model saw).
   if (web !== null) {
     const settled = 'kind' in material.block ? material.block : null
     const body = settled === null ? '' : resultText(settled)

packages/client/ui-conversation/tests/web-card.spec.tsx

@@ -17,7 +17,7 @@ import type {
 import type { ToolResultView } from '@deepseek-ai/dsh-client-connection/client'
 import { bindSnapshotSelector } from '@deepseek-ai/dsh-client-web-react'
 import type { SelectionTarget, ToolRowOwnerProps } from '@deepseek-ai/dsh-client-ui-conversation/client'
-import { CHAT_WEB_MAX_SOURCES, webCardModel } from '../src/client/contract/web-card-model.ts'
+import { webCardModel } from '../src/client/contract/web-card-model.ts'
 import { createChatStore } from '../src/client/stores.ts'
 import { GenericToolCard } from '../src/client/chat/GenericToolCard.tsx'
 import { DetailsPanel } from '../src/client/skeleton/DetailsPanel.tsx'
@@ -135,8 +135,7 @@ describe('chat row web body', () => {
     fireEvent.click(view.container.querySelector('[data-expandable]')!)
   }
 
-  it('the WebRow collapses to the summary row, expanding to the search card capped tighter than the panel', () => {
-    expect(CHAT_WEB_MAX_SOURCES).toBeLessThan(16)
+  it('the WebRow collapses to the summary row, expanding to the full search card', () => {
     const view = render(<WebRow {...rowProps(settledSearch(), 'web_search')} />)
     // Collapsed: the summary row alone, no card in the DOM.
     expect(view.getByText('Search')).toBeTruthy()