fix(ListItem): support ReactNode for description prop, fix whiteSpace nowrap breaking line-clamp

[cixzhang]

Summary

Fixes #890 — two related issues with XDSListItem:

1. description prop now accepts ReactNode

Changed from string to ReactNode so consumers can pass rich content (multiple text elements, conditional rendering, inline truncation):

<XDSListItem
  label={item.title}
  description={
    <div>
      {item.snippet != null && (
        <XDSText type="supporting" maxLines={2}>{item.snippet}</XDSText>
      )}
      {item.creationTime != null && (
        <XDSText type="supporting">
          {formatRelativeTime(item.creationTime)}
        </XDSText>
      )}
    </div>
  }
/>

Backward compatible — plain strings still work exactly as before (single-line truncation applied automatically).

2. Fix whiteSpace: 'nowrap' breaking -webkit-line-clamp

The description wrapper previously applied whiteSpace: 'nowrap' unconditionally. This silently broke any child component using -webkit-line-clamp (e.g. maxLines on XDSText) because line-clamp requires text to be allowed to wrap.

Fix: Split into two style objects — descriptionString (with whiteSpace: nowrap + textOverflow: ellipsis) applied only when description is a plain string; the base description style has no wrapping constraints for ReactNode.

Changes

• packages/core/src/List/XDSListItem.tsx — type change, split description styles, conditional style application
• packages/core/src/List/List.doc.mjs — updated description prop type in docs
• packages/core/src/List/XDSList.test.tsx — 3 new tests for ReactNode description variants

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[github-actions]

PR Analysis Report

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Modified Components

List · View in Storybook

Metric	Before	After	Delta
Bundle Size (ESM)	N/A	292B	N/A
Lines of Code	N/A	400	-
Complexity	N/A	Very High (36)	-

Bundle Size Summary

Package	Size (ESM)	Size (CJS)	Gzipped
@xds/core	11.1KB	17.6KB	2.7KB

Accessibility Audit

Status: 1 accessibility violation(s) found — 1 critical.

XDSList - 1 issue(s)

• 🔴 critical: Ensure an element's role supports its ARIA attributes
  • Rule: aria-allowed-attr · Affects 1/10 stories · Learn more
  • WCAG: 4.1.2 (Level A)

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