Replace unsafe/legacy types in ui-kit/experimental

[fpigeonjr]

Parent

#586

What to build

Replace unsafe and legacy TypeScript types (any, unsafe function types, wrapper-object types) across src/ui-kit/experimental (~134 ESLint findings).

Inventory the current findings first (npx eslint src/ui-kit/experimental), then replace each any/unsafe-function-type usage with a precise type or a justified, narrowly-scoped alternative, following the same approach used in #702 (utilities/directives/layout/misc slice of the same parent issue).

Largest concentrations of findings as of this writing:

• patterns/layout/architecture/service/service-property.ts (17)
• date-range-v2/datepicker/calendar.ts (14)
• hierarchical/hierarchical-test-service.spec.ts (10)
• listbox/listbox.component.ts (9)
• hierarchical/hierarchical/hierarchical.component.ts, hierarchical/autocomplete/autocomplete.component.ts, hierarchical/selected-result/selected-result.component.ts, patterns/layout/architecture/store/datastore.ts (7-8 each)
• aria/abstract-combobox/abstract-combobox.ts, hierarchical/hierarchical-tree-grid/data-source.ts, input-mask/input-mask.component.ts (4-6 each)
• Remaining findings scattered across aria/abstract-grid, aria/utils/events.ts, date-range-v2, dollar, video-player, actions-list, button-next, patterns/layout model/service/component files, search, tabs, title, and spec files

Given the size of this area, expect this to likely produce a larger PR than the other sub-issues; consider further splitting (e.g. hierarchical/* vs. patterns/layout/* vs. everything else) once work begins if a single PR proves unwieldy.

Acceptance criteria

• Unsafe-type findings in src/ui-kit/experimental are inventoried before implementation
• any usages in this directory are replaced with precise types or justified, narrowly scoped alternatives
• Any wrapper-object or unsafe function types in this directory are replaced with safe equivalents
• Public API and consumer-compiled source compatibility are preserved (no breaking signature changes)
• Relevant component tests and the full test-app suite remain green
• The root ESLint warning baseline (eslint-baseline.json) is lowered to reflect the resolved findings

Blocked by

None - can start immediately