feat(tables): add tree support

[tenphi]

Summary

• add opt-in nested rows to ItemTable and DataTable with controlled and uncontrolled expansion
• add React Aria treegrid semantics, disclosure controls, roving focus, typeahead, and hierarchy keyboard navigation
• make client sorting, search, pagination, virtualization, ranges, selection, and row drops hierarchy-aware
• add cascading ItemTable selection, recursive DataTable sorting, stories, docs, localization, browser coverage, and a minor changeset
• raise the complete bundle budget from 505 kB to 510 kB; the measured bundle is 508.04 kB and the Button tree-shaking budget is unchanged

Verification

• pnpm test — 97 files, 2,079 passed, 1 skipped
• pnpm test:browser — 8 files, 110 passed
• pnpm audit-docs --component=ItemTable
• pnpm audit-docs --component=DataTable
• pnpm audit-defaults
• pnpm build
• pnpm size

---

Note

High Risk
Touches core table rendering, selection, virtualization, and keyboard/ARIA behavior. Hierarchy-aware sort, search, pagination, ranges, and cascade selection can regress existing grids if the new paths leak into flat tables.

Overview
Adds opt-in nested rows to ItemTable and DataTable via getRowChildren, with controlled/uncontrolled expansion, React Aria treegrid semantics, disclosure chrome, and hierarchy keyboard navigation (including virtualized focus).

Shared table-tree operations make sort, search, pagination, virtualization, cell ranges, and drops hierarchy-aware. ItemTable multiple selection can cascade (or stay independent); DataTable sorts recursively per sibling group. Column reordering is ignored in tree mode; dropOnRow rejects self/descendant cycles.

DataTable also accepts nested column groups for multi-row pivot headers (scope="colgroup" / colSpan). Leaf columns still sort and resize; drag reordering is disabled while groups exist.

Both tables gain isAutoHeight, which shrink-wraps the frame to rendered rows, wins over flex/height sizing, and turns virtualization off. Bundle budget rises 505→510 kB; Button-only tree-shaking is unchanged.

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[changeset-bot]

🦋 Changeset detected

Latest commit: bdcaf1a

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@cube-dev/ui-kit	Minor

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Project	Deployment	Actions	Updated (UTC)
cube-ui-kit	Ready	Preview	Aug 21, 2026 9:01am

[github-actions]

📦 NPM canary release

Deployed canary version 0.0.0-canary-d05b057.

[github-actions]

🧪 Storybook is successfully deployed!

• 👀 Review changes: https://www.chromatic.com/build?appId=626ee6db91d1c8004a912249&number=3934
• 👨‍🎨 Preview storybook: https://626ee6db91d1c8004a912249-ifyxfzpcgh.chromatic.com/

[github-actions]

🏋️ Size limit report

Name	Size	Passed?
All	497.05 KB (+0.93% 🔺)	Yes 🎉
Tree shaking (just a Button)	120.73 KB (0% 🟰)	Yes 🎉

Compared against main at 11e8319 — run 32383738012, 2026-08-20T15:02:21Z.

To see which modules changed, download the size-limit-statoscope-report artifact from this run and open report.html.

[cursor]

Cursor Bugbot has reviewed your changes using default effort and found 1 potential issue.

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