feat(calendar): migrate to react-day-picker v9 and polish UI
- Update classNames and CSS import (style.css)
- Custom Dropdown via shadcn Select
- Nav arrows aligned with caption (around)
- Today highlight with cyan tone, weekdays in sentence case
- Wider layout to avoid overflow; remove inner wrapper
chore(tickets): make 'Patrimônio do computador (se houver)' optional
- Backend hotfix to enforce optional + label on existing tenants
- Hide required asterisk for this field in portal/new-ticket
refactor(new-ticket): remove channel dropdown from admin/agent flow
- Keep default channel as MANUAL
feat(ux): simplify requester section and enlarge combobox trigger
- Remove RequesterPreview redundancy; show company badge in trigger
