fix: repair failing tests across ui/utils/web packages

[stooit]

Summary

Fixes all failing tests and type errors in the monorepo. Baseline was 8 pass / 5 fail plus 5 type errors; now 13 pass / 0 fail and tsc --noEmit is clean.

Four cross-package bugs plus one test-config fix:

• apps/web/src/lib/api.ts — imported useThrottle from @e2e/utils, but that hook was renamed to useDebounce. Updated the import and the useSearchDebounce re-export alias. (Fixes TS2305 + runtime crash.)
• packages/ui/.../Button.tsx — the destructured aria-label prop was never applied to the element. Now applied; icon-only buttons fall back to their string children (or "Button") and emit a dev-mode warning when unlabelled (WCAG 2.2 SC 4.1.2). Text buttons resolve to undefined so their visible text remains the accessible name.
• packages/utils/.../date.ts — formatDate produced a zero-padded day (01/03/2024); the contract is D/MM/YYYY with an unpadded day. Assembled from Intl.DateTimeFormat.formatToParts under en-AU. (dateStyle: "short" deliberately avoided — it would drop the year to 2 digits.)
• packages/ui/.../DataTable.tsx — sort-direction toggle read a stale sortDir from its closure; switched to the functional setSortDir(prev => ...) form so it always reads the latest committed value (matters under React 18 automatic batching).
• tsconfig.json — added "types": ["bun-types"] so bun:test resolves in the test files (fixes 4× TS2307).

Testing

• bun test --preload ./packages/ui/test/setup.ts → 13 pass, 0 fail
• npx tsc --noEmit → clean (exit 0)
• No test files were modified.

Assumptions & notes

• formatDate now returns variable-width day (1/03/2024 vs 15/06/2024), as the test mandates. Only in-repo consumer is the api.ts re-export; no fixed-width formatting depends on it.
• The DataTable stale-closure fix is correct but the existing test passes both before and after (each fireEvent.click gets its own act()); a batched-click test would lock it in but that requires a test-file change, which was out of scope.
• aria-label="Button" satisfies the assertion mechanically; the dev-mode warning is the real remediation nudging callers to supply a meaningful label.