Fix CI failures: export StackSchema, add chart-bar color default, remove unused param

[Copilot]

CI build failing with TypeScript errors and test failure in workflow run #21089060389.

Changes:

• Export StackSchema type — Added to @object-ui/types public API and LayoutSchema union. The type was defined but not exported, breaking imports in packages/components/src/renderers/layout/stack.tsx.

• Add color: '#8884d8' to chart-bar defaultProps — Test expected this default but it was missing from the component registration.

• Remove unused isChild parameter — TreeNodeComponent declared but never read the parameter, causing TS6133 warning.

Diff summary:

packages/types/src/index.ts     +1 (export StackSchema)
packages/types/src/layout.ts    +1 (add to union)
packages/plugin-charts/src/     +1 (color default)
packages/components/src/        -3 (remove isChild)

Original prompt

引用: https://github.com/objectstack-ai/objectui/actions/runs/21089060389/job/60658962048#step:7:1

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Project	Deployment	Review	Updated (UTC)
objectui-docs	Error		Jan 17, 2026 11:41am

[github-actions]

✅ All checks passed!

• ✅ Type check passed
• ✅ Tests passed
• ✅ Lint check completed

[Copilot]

Pull request overview

This PR addresses CI build failures caused by TypeScript compilation errors and a failing test. The changes are targeted fixes to resolve import errors, missing type exports, a test assertion failure, and unused parameter warnings.

Changes:

• Exported StackSchema from the types package to fix import error in stack component renderer
• Added color: '#8884d8' default to chart-bar component registration to satisfy test expectations
• Removed unused isChild parameter from TreeNodeComponent to eliminate TypeScript warning

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

File	Description
packages/types/src/index.ts	Added StackSchema to public type exports to fix import error in stack.tsx
packages/types/src/layout.ts	Added StackSchema to LayoutSchema union type for completeness
packages/plugin-charts/src/index.tsx	Added missing color default property to fix failing test assertion
packages/components/src/renderers/data-display/tree-view.tsx	Removed unused isChild parameter and its usage to eliminate TS6133 warning