fix: repair cross-package test failures across ui, utils, and web

[stooit]

Summary

Fixes all failing tests and type errors in the monorepo. Root cause was four distinct cross-package bugs plus a missing type reference. Final state: 13/13 tests pass, tsc --noEmit exits 0.

Bugs fixed

• @e2e/utils renamed hook — apps/web/src/lib/api.ts imported useThrottle, which no longer exists; the hook is exported as useDebounce. Updated the consumer import to the correct name, resolving both the api module test failure and the TS2305 type error.
• formatDate format — output was 01/03/2024; the test requires 1/03/2024 (day-first, numeric day with no leading zero). Adjusted the format so the day is numeric while preserving day/month/year order. Other date/currency tests unaffected.
• Button accessibility — the component was not forwarding aria-label to the underlying <button>, so icon-only buttons had no accessible name. Now forwards the label to the DOM element; for icon-only buttons with no explicit label it falls back to a minimal accessible name rather than an empty string (WCAG 4.1.2).
• DataTable stale closure — the sort handler read a stale state value, so a second click never toggled to descending. Switched to the functional-updater form of the state setter so repeated clicks toggle direction correctly.

Tooling

• tsconfig.json — added "types": ["bun-types"] (already installed in node_modules, no new dependency) so bun:test resolves in test files, clearing the last tsc errors.

Verification

• bun run test → 13 pass / 0 fail
• bunx tsc --noEmit → exit 0

Notes / assumptions

• No test files were modified and no dependencies were added, per task constraints.
• For icon-only buttons lacking an explicit aria-label, a minimal default accessible name is applied so the button is never nameless to assistive tech.
• Changes were independently reviewed (verdict: approve) before commit.