- toggleCompanyHoliday now calls loadStats() so the entitlement sidebar
updates immediately when a vacation day is converted to a company holiday
- deleteYear now deletes vacay_user_years rows for the removed year,
preventing stale entitlement data from persisting and re-appearing
when the year is re-created
- deleteYear recalculates carry-over for year+1 when year N is deleted,
using the new actual previous year as the source
- removeYear store action now calls loadStats() so the sidebar reflects
the recalculated carry-over without requiring a page refresh
- Add prev-year button (+[<] 2026 [>]+) so users can add years going
backwards after deleting a past year; add vacay.addPrevYear i18n key
to all 13 supported languages
Closes#371
jubnl