Added analytics by transactions

backend/src/domain/transaction.go

@@ -46,3 +46,16 @@ type TransactionListFilter struct {
 	Limit     int
 	Offset    int
 }
+
+type TransactionAnalyticsFilter struct {
+	FamilyID *int64
+	Type     *string
+	DateFrom time.Time
+	DateTo   time.Time
+}
+
+type TransactionAnalytics struct {
+	Expenses float64
+	Incomes  float64
+	Total    float64
+}