feat(web): render grep/glob search output as a search card

Consume the card:'search' result view (matches grouped by file for grep, a
path list for glob) the search backend PR added. SearchBlock (ui-primitives)
draws both kinds via the kind discriminant with a per-file collapse, a
truncation pill, a height cap matching TerminalBlock, and a copy control;
search-card-model is the single resultView derivation; a keyed SearchRow
registers under grep and glob with the card resident under its summary. The
generic fallback and the details panel are search-aware. Fixture gains grep and
glob turns for the built-boot snapshot.

packages/client/ui-primitives/src/index.ts

@@ -22,6 +22,10 @@ export { JsonTree } from './JsonTree.tsx'
 export type { JsonTreeProps } from './JsonTree.tsx'
 export { TerminalBlock, DEFAULT_TERMINAL_MAX_LINES } from './TerminalBlock.tsx'
 export type { TerminalBlockProps } from './TerminalBlock.tsx'
+export { SearchBlock, DEFAULT_SEARCH_MAX_LINES } from './SearchBlock.tsx'
+export type {
+  SearchBlockProps, SearchMatchesBlockProps, SearchPathsBlockProps, SearchFileGroup, SearchBlockLineMatch,
+} from './SearchBlock.tsx'
 export { CodeBlock } from './markdown/CodeBlock.tsx'
 export { JsonBlock } from './markdown/JsonBlock.tsx'
 export { MarkdownText } from './markdown/MarkdownText.tsx'