M9.1: wire sync logging into all mutation paths

- Add LogClosedDayDelete and LogClosedWeekDelete to SyncStore
- Inject syncStore into EntryService; log Start, Stop, StopByID,
  Update, CreateInterval, Delete, AutoStopStalledEntries
- Inject syncStore into DayService; log CloseDay, MarkDay, ReopenDay,
  and the recomputeWeek closed-week upsert
- Inject syncStore into SettingsService; log Upsert, UpdateSettings,
  DeleteSettings
- Add LogClosedWeek/LogClosedWeekDelete calls in WeekService.CloseWeek
  and ReopenWeek
- Update main.go and all service test helpers for new constructor signatures
- All Go tests and 19 Vitest tests pass

internal/store/sync_store.go

@@ -150,6 +150,12 @@ func (s *SyncStore) LogClosedDay(ctx context.Context, d *domain.ClosedDay) error
 	return s.log(ctx, "closed_days", d.DayKey, "upsert", string(payload))
 }
 
+// LogClosedDayDelete appends a closed_day delete to the sync log.
+func (s *SyncStore) LogClosedDayDelete(ctx context.Context, dayKey string) error {
+	payload := fmt.Sprintf(`{"day_key":%q}`, dayKey)
+	return s.log(ctx, "closed_days", dayKey, "delete", payload)
+}
+
 // LogClosedWeek appends a closed_week upsert to the sync log.
 func (s *SyncStore) LogClosedWeek(ctx context.Context, w *domain.ClosedWeek) error {
 	payload, err := json.Marshal(w)
@@ -159,6 +165,12 @@ func (s *SyncStore) LogClosedWeek(ctx context.Context, w *domain.ClosedWeek) err
 	return s.log(ctx, "closed_weeks", w.WeekKey, "upsert", string(payload))
 }
 
+// LogClosedWeekDelete appends a closed_week delete to the sync log.
+func (s *SyncStore) LogClosedWeekDelete(ctx context.Context, weekKey string) error {
+	payload := fmt.Sprintf(`{"week_key":%q}`, weekKey)
+	return s.log(ctx, "closed_weeks", weekKey, "delete", payload)
+}
+
 // LogSettings appends a settings upsert to the sync log.
 func (s *SyncStore) LogSettings(ctx context.Context, set *domain.Settings) error {
 	payload, err := json.Marshal(set)