fix(tree,treeselect,organizationchart): enable generic type inference for value/options and slots

[YevheniiKotyrlo]

Defect Fixes

Fixes #8496

Tree, TreeSelect, and OrganizationChart use TreeNode / OrganizationChartNode for their data props and all slot scoped data. Both interfaces have a [key: string]: any index signature. Developers who extend these interfaces with custom properties get no type safety — custom properties resolve to any via the index signature instead of their declared types.

Same root cause as #8442 — DefineComponent's no-arg constructor prevents generic inference. Same fix pattern as #8444 (DataTable/DatePicker).

Related: #7426, #6041

Reproducer: StackBlitz — bun run type-check (0 errors, typo undetected) → bun run patch && bun run type-check (TS2339 catches it)

Problem

interface MyTreeNode extends TreeNode {
  customLabel: string;
  customIcon?: string;
}

const nodes: MyTreeNode[] = [
  { key: '1', customLabel: 'Root', children: [] }
];

<Tree :value="nodes">
  <template #default="{ node }">
    {{ node.customLabel }}
    <!-- No error — `node.customLabel` is `any` (from index signature), typo ships to production -->
  </template>
</Tree>

After this fix, TypeScript infers T = MyTreeNode from the :value binding and flows it to all slots:

<Tree :value="nodes">
  <template #default="{ node }">
    {{ node.customLabel }}
    <!-- node.customLabel is `string` — proper type from MyTreeNode -->
  </template>
</Tree>

Changes

Tree:

• TreeProps<T extends TreeNode = TreeNode> — value: T[], filterBy callback (node: T) => string
• TreeSlots<T extends TreeNode = TreeNode> — all 5+ slots with node: T, catch-all [key: string]: (node: T) => VNode[]
• Generic constructor replaces DefineComponent

TreeSelect:

• TreeSelectProps<T extends TreeNode = TreeNode> — options: T[], modelValue: T | any, filterBy callback (node: T) => string
• TreeSelectSlots<T extends TreeNode = TreeNode> — node: T in option/toggle slots (removes incorrect | any), options: T[] in header/footer
• Generic constructor with & TreeSelectMethods

OrganizationChart:

• OrganizationChartProps<T extends OrganizationChartNode = OrganizationChartNode> — value: T
• OrganizationChartSlots<T extends OrganizationChartNode = OrganizationChartNode> — node: T in default slot, catch-all [key: string]: (node: T) => VNode[]
• Generic constructor replaces DefineComponent

What gets typed

Slot / Prop	Before	After
Tree #default node	TreeNode	T
Tree #nodeicon / #nodetoggleicon node	TreeNode	T
Tree catch-all [key: string] node	any	T
TreeSelect #option node	TreeNode | any	T
TreeSelect #header / #footer options	TreeNode[]	T[]
OrganizationChart #default node	any	T
OrganizationChart catch-all [key: string] node	any	T

Scope / Impact

• No breaking changes — backward compatible, T defaults to TreeNode / OrganizationChartNode
• No runtime changes — types only (.d.ts files)
• 3 components: Tree, TreeSelect, OrganizationChart

Verification

Gate	Result
pnpm run format:check	PASS
pnpm run lint	PASS
pnpm run test:unit	Pre-existing failures only, 0 new
pnpm run build:packages	Pre-existing Windows build issue (NODE_ENV= syntax), 0 new

Series

This is part of a series bringing generic type inference to all PrimeVue data components:

PR	Components	Status
#8444	DataTable, DatePicker	Open
#8484	Select, MultiSelect, Listbox	Open
#8485	Column (phantom of prop)	Open
#8489	AutoComplete, CascadeSelect, DataView	Open
#8490	Carousel, Galleria, Timeline	Open
#8491	OrderList, PickList	Open
#8493	VirtualScroller, SelectButton, InputChips	Open
#8495	Menubar, Menu, TieredMenu, MegaMenu, ContextMenu, PanelMenu, Breadcrumb, Steps, TabMenu, SplitButton, Dock, SpeedDial	Open
#8497	Tree, TreeSelect, OrganizationChart	This PR

After this series, every PrimeVue component with a collection prop will infer T from the binding and flow it to slots — giving developers full IDE autocomplete and compile-time type safety in templates.