feat(#21): contas bancárias e patrimônio consolidado

CRUD de contas (corrente/poupança/investimento/cartão) com saldo calculado
automaticamente. account_id nullable em transactions. Widget patrimônio no
dashboard. Tela /contas. Seletor de conta nas transações manuais.

Co-Authored-By: Claude Sonnet 4.6 <[email protected]>

apps/api/internal/service/dashboard.go

@@ -13,13 +13,18 @@ type DashboardRepo interface {
 	RecentTransactions(ctx context.Context, month string) ([]model.RecentTransaction, error)
 }
 
-type DashboardService struct {
-	repo      DashboardRepo
-	recurrSvc *RecurringService
+type PatrimonySource interface {
+	TotalPatrimony(ctx context.Context) (float64, error)
 }
 
-func NewDashboardService(repo DashboardRepo, recurrSvc *RecurringService) *DashboardService {
-	return &DashboardService{repo: repo, recurrSvc: recurrSvc}
+type DashboardService struct {
+	repo       DashboardRepo
+	recurrSvc  *RecurringService
+	patrimony  PatrimonySource
+}
+
+func NewDashboardService(repo DashboardRepo, recurrSvc *RecurringService, patrimony PatrimonySource) *DashboardService {
+	return &DashboardService{repo: repo, recurrSvc: recurrSvc, patrimony: patrimony}
 }
 
 func (s *DashboardService) Get(ctx context.Context, month string) (*model.DashboardData, error) {
@@ -69,11 +74,17 @@ func (s *DashboardService) Get(ctx context.Context, month string) (*model.Dashbo
 		recent = []model.RecentTransaction{}
 	}
 
+	patrimony, err := s.patrimony.TotalPatrimony(ctx)
+	if err != nil {
+		return nil, err
+	}
+
 	return &model.DashboardData{
 		Month:              month,
 		TotalIncome:        income,
 		TotalExpenses:      expenses,
 		SavingsPct:         savingsPct,
+		TotalPatrimony:     patrimony,
 		ByCategory:         byCategory,
 		MonthlyEvolution:   evolution,
 		RecentTransactions: recent,