fix: skip untracked workdays when closing a week

Previously any past workday without a closed_days record blocked week
close. Now only days that actually have entries require an explicit
close. Empty workdays count as 0h worked, which is reflected in the
weekly delta automatically.

- WeekService.CloseWeek: after finding no closed_days record, check
  whether the day has any entries; only error if it does
- NewWeekService: takes EntryStore to support the above check
- Updated TestCloseWeekMissingDayFails to reflect the new semantic
  (test now creates entries on Friday but leaves it unclosed)

internal/service/week_service.go

@@ -15,6 +15,7 @@ import (
 type WeekService struct {
 	closedDays  *store.ClosedDayStore
 	closedWeeks *store.ClosedWeekStore
+	entries     *store.EntryStore
 	settings    *store.SettingsStore
 	db          interface {
 		QueryRowContext(ctx context.Context, query string, args ...interface{}) *sql.Row
@@ -26,6 +27,7 @@ type WeekService struct {
 func NewWeekService(
 	closedDays *store.ClosedDayStore,
 	closedWeeks *store.ClosedWeekStore,
+	entries *store.EntryStore,
 	settings *store.SettingsStore,
 	rawDB *sql.DB,
 	tz *time.Location,
@@ -33,6 +35,7 @@ func NewWeekService(
 	return &WeekService{
 		closedDays:  closedDays,
 		closedWeeks: closedWeeks,
+		entries:     entries,
 		settings:    settings,
 		rawDB:       rawDB,
 		tz:          tz,
@@ -88,8 +91,9 @@ func (s *WeekService) CloseWeek(ctx context.Context, weekKey string) (*domain.Cl
 	// Compute expected ms for the week (from settings frozen at week start)
 	expectedMs := int64(set.HoursPerWeek * 3_600_000)
 
-	// Verify all workdays up to and including today are closed; collect worked ms.
-	// Future workdays in the week (not yet reached) are skipped.
+	// Verify all past workdays that have entries are closed; collect worked ms.
+	// Past workdays with no entries at all are skipped (they contribute 0h).
+	// Future workdays in the week are always skipped.
 	todayKey := time.Now().In(s.tz).Format("2006-01-02")
 	var totalWorkedMs int64
 	for _, dk := range dayKeys {
@@ -101,13 +105,23 @@ func (s *WeekService) CloseWeek(ctx context.Context, weekKey string) (*domain.Cl
 			continue // future workday — skip
 		}
 		cd, err := s.closedDays.GetByDayKey(ctx, dk)
-		if err != nil {
-			if errors.Is(err, sql.ErrNoRows) {
-				return nil, fmt.Errorf("%w: %s", ErrWeekHasUnclosedDays, dk)
-			}
+		if err != nil && !errors.Is(err, sql.ErrNoRows) {
 			return nil, err
 		}
-		totalWorkedMs += cd.WorkedMs
+		if cd != nil {
+			totalWorkedMs += cd.WorkedMs
+			continue
+		}
+		// No closed_days record — check whether the day has any entries.
+		dayEntries, err := s.entries.ListByDayKey(ctx, dk)
+		if err != nil {
+			return nil, err
+		}
+		if len(dayEntries) > 0 {
+			// Day has tracked time but was never closed — require explicit close.
+			return nil, fmt.Errorf("%w: %s", ErrWeekHasUnclosedDays, dk)
+		}
+		// No entries, no closed record → untracked day, counts as 0h.
 	}
 
 	now := time.Now().UnixMilli()