feat: configurable weekend days in Vacay — closes #97

Users can now select which days are weekends (default: Sat+Sun).
Useful for countries like Bangladesh (Fri+Sat) or others with
different work weeks. Settings appear under "Block weekends" toggle.

client/src/components/Vacay/VacayCalendar.tsx

@@ -26,6 +26,7 @@ export default function VacayCalendar() {
   }, [entries])
 
   const blockWeekends = plan?.block_weekends !== false
+  const weekendDays: number[] = plan?.weekend_days ? String(plan.weekend_days).split(',').map(Number) : [0, 6]
   const companyHolidaysEnabled = plan?.company_holidays_enabled !== false
 
   const handleCellClick = useCallback(async (dateStr) => {
@@ -35,7 +36,7 @@ export default function VacayCalendar() {
       return
     }
     if (holidays[dateStr]) return
-    if (blockWeekends && isWeekend(dateStr)) return
+    if (blockWeekends && isWeekend(dateStr, weekendDays)) return
     if (companyHolidaysEnabled && companyHolidaySet.has(dateStr)) return
     await toggleEntry(dateStr, selectedUserId || undefined)
   }, [companyMode, toggleEntry, toggleCompanyHoliday, holidays, companyHolidaySet, blockWeekends, companyHolidaysEnabled, selectedUserId])
@@ -57,6 +58,7 @@ export default function VacayCalendar() {
             onCellClick={handleCellClick}
             companyMode={companyMode}
             blockWeekends={blockWeekends}
+            weekendDays={weekendDays}
           />
         ))}
       </div>

client/src/components/Vacay/VacayMonthCard.tsx

@@ -29,11 +29,12 @@ interface VacayMonthCardProps {
   onCellClick: (date: string) => void
   companyMode: boolean
   blockWeekends: boolean
+  weekendDays?: number[]
 }
 
 export default function VacayMonthCard({
   year, month, holidays, companyHolidaySet, companyHolidaysEnabled = true, entryMap,
-  onCellClick, companyMode, blockWeekends
+  onCellClick, companyMode, blockWeekends, weekendDays = [0, 6]
 }: VacayMonthCardProps) {
   const { language } = useTranslation()
   const weekdays = language === 'de' ? WEEKDAYS_DE : language === 'es' ? WEEKDAYS_ES : language === 'ar' ? WEEKDAYS_AR : WEEKDAYS_EN
@@ -76,7 +77,8 @@ export default function VacayMonthCard({
               if (day === null) return <div key={di} style={{ height: 28 }} />
 
               const dateStr = `${year}-${pad(month + 1)}-${pad(day)}`
-              const weekend = di >= 5
+              const dayOfWeek = new Date(year, month, day).getDay()
+              const weekend = weekendDays.includes(dayOfWeek)
               const holiday = holidays[dateStr]
               const isCompany = companyHolidaysEnabled && companyHolidaySet.has(dateStr)
               const dayEntries = entryMap[dateStr] || []

client/src/components/Vacay/VacaySettings.tsx

@@ -49,6 +49,42 @@ export default function VacaySettings({ onClose }: VacaySettingsProps) {
         onChange={() => toggle('block_weekends')}
       />
 
+      {/* Weekend days selector */}
+      {plan.block_weekends !== false && (
+        <div style={{ paddingLeft: 36 }}>
+          <p className="text-xs font-medium mb-2" style={{ color: 'var(--text-muted)' }}>{t('vacay.weekendDays')}</p>
+          <div className="flex flex-wrap gap-1.5">
+            {[
+              { day: 1, label: t('vacay.mon') },
+              { day: 2, label: t('vacay.tue') },
+              { day: 3, label: t('vacay.wed') },
+              { day: 4, label: t('vacay.thu') },
+              { day: 5, label: t('vacay.fri') },
+              { day: 6, label: t('vacay.sat') },
+              { day: 0, label: t('vacay.sun') },
+            ].map(({ day, label }) => {
+              const current: number[] = plan.weekend_days ? String(plan.weekend_days).split(',').map(Number) : [0, 6]
+              const active = current.includes(day)
+              return (
+                <button key={day} onClick={() => {
+                  const next = active ? current.filter(d => d !== day) : [...current, day]
+                  updatePlan({ weekend_days: next.join(',') })
+                }}
+                  style={{
+                    padding: '4px 10px', borderRadius: 8, fontSize: 12, fontWeight: 600, cursor: 'pointer',
+                    fontFamily: 'inherit', border: '1px solid', transition: 'all 0.12s',
+                    background: active ? 'var(--text-primary)' : 'var(--bg-card)',
+                    borderColor: active ? 'var(--text-primary)' : 'var(--border-primary)',
+                    color: active ? 'var(--bg-primary)' : 'var(--text-muted)',
+                  }}>
+                  {label}
+                </button>
+              )
+            })}
+          </div>
+        </div>
+      )}
+
       {/* Carry-over */}
       <SettingToggle
         icon={ArrowRightLeft}

client/src/components/Vacay/holidays.ts

@@ -103,10 +103,9 @@ export function getHolidays(year: number, bundesland: string = 'NW'): Record<str
   return holidays
 }
 
-export function isWeekend(dateStr: string): boolean {
+export function isWeekend(dateStr: string, weekendDays: number[] = [0, 6]): boolean {
   const d = new Date(dateStr + 'T00:00:00')
-  const day = d.getDay()
-  return day === 0 || day === 6
+  return weekendDays.includes(d.getDay())
 }
 
 export function getWeekday(dateStr: string): string {

server/src/routes/vacay.ts

@@ -196,7 +196,7 @@ router.get('/plan', (req: Request, res: Response) => {
 router.put('/plan', async (req: Request, res: Response) => {
   const authReq = req as AuthRequest;
   const planId = getActivePlanId(authReq.user.id);
-  const { block_weekends, holidays_enabled, holidays_region, company_holidays_enabled, carry_over_enabled } = req.body;
+  const { block_weekends, holidays_enabled, holidays_region, company_holidays_enabled, carry_over_enabled, weekend_days } = req.body;
 
   const updates: string[] = [];
   const params: (string | number)[] = [];
@@ -205,6 +205,7 @@ router.put('/plan', async (req: Request, res: Response) => {
   if (holidays_region !== undefined) { updates.push('holidays_region = ?'); params.push(holidays_region); }
   if (company_holidays_enabled !== undefined) { updates.push('company_holidays_enabled = ?'); params.push(company_holidays_enabled ? 1 : 0); }
   if (carry_over_enabled !== undefined) { updates.push('carry_over_enabled = ?'); params.push(carry_over_enabled ? 1 : 0); }
+  if (weekend_days !== undefined) { updates.push('weekend_days = ?'); params.push(String(weekend_days)); }
 
   if (updates.length > 0) {
     params.push(planId);