fix: repair cross-package bugs and test DOM/type setup

[stooit]

Summary

Fixes all failing bun test cases and tsc --noEmit errors across the monorepo. Bugs spanned three packages plus the shared test/type configuration. All 13 tests now pass and tsc --noEmit is clean.

Changes

Package	File	Fix
apps/web	src/lib/api.ts	useThrottle was renamed to useDebounce in packages/utils; updated the import and the useSearchDebounce re-export to the new name.
packages/ui	src/components/Button/Button.tsx	Icon-only buttons never applied the destructured ariaLabel. Now wired to the <button> element.
packages/ui	src/components/DataTable/DataTable.tsx	Stale-closure bug in the sort handler — setSortDir read a captured sortDir. Switched to the functional updater form so a second click sorts descending.
packages/utils	src/format/date.ts	Short date used US month-first order. Switched to en-AU day/month/year to match the expected format.
root + ui	bunfig.toml, packages/ui/bunfig.toml	environment = "happy-dom" alone does not inject DOM globals in bun 1.3.14. Added preload of the @happy-dom/global-registrator setup so a bare bun test from the repo root has document/window.
root	tsconfig.json	Added "types": ["bun-types"] so bun:test globals type-check under tsc --noEmit.

Verification

bun test         # 13 pass, 0 fail across 5 files
npx tsc --noEmit # clean, exit 0

Constraints honored

• No test files modified.
• No new dependencies added (happy-dom and bun-types were already installed).
• Changes are minimal — 7 files, +10/-12 lines — each maps directly to a failing test or type error.