完善生图5.0的功能

backend/internal/postgres/generation_state.go

@@ -51,7 +51,11 @@ func (db *Database) ChargeAndActivateCreation(ctx context.Context, request billi
 	}
 	var posting WalletEntry
 	if !rows.Next() {
+		rowsErr := rows.Err()
 		rows.Close()
+		if rowsErr != nil {
+			return nil, fmt.Errorf("charge and activate generation creation: read wallet: %w", rowsErr)
+		}
 		return nil, fmt.Errorf("charge and activate generation creation: wallet returned no row")
 	}
 	if err := rows.Scan(&posting.LedgerID, &posting.BalanceAfterFen, &posting.BalanceFen, &posting.TotalRechargedFen, &posting.TotalChargedFen, &posting.CreatedAt, &posting.UpdatedAt, &posting.DeltaFen); err != nil {
@@ -79,7 +83,11 @@ func (db *Database) ChargeAndActivateCreation(ctx context.Context, request billi
 		return nil, fmt.Errorf("charge and activate generation creation: activate job: %w", err)
 	}
 	if !activation.Next() {
+		rowsErr := activation.Err()
 		activation.Close()
+		if rowsErr != nil {
+			return nil, fmt.Errorf("charge and activate generation creation: read activation: %w", rowsErr)
+		}
 		return nil, fmt.Errorf("charge and activate generation creation: job is not pending")
 	}
 	var id string

backend/internal/postgres/generation_state_test.go

@@ -48,6 +48,34 @@ func TestChargeAndActivateCreationRollsBackWhenActivationFails(t *testing.T) {
 	}
 }
 
+func TestChargeAndActivateCreationPreservesDeferredWalletError(t *testing.T) {
+	deferred := &pgconn.PgError{Code: "P0001", Message: "BILLING_INSUFFICIENT_BALANCE"}
+	tx := &generationStateTransaction{results: []*jobRows{{err: deferred}}}
+	db := NewDatabase(Config{Backend: BackendPostgres}, &generationStatePool{tx: tx})
+
+	_, err := db.ChargeAndActivateCreation(context.Background(), billing.ChargeRequest{OrganizationID: "org", JobID: "job", AmountFen: 39}, json.RawMessage(`{"status":"pending"}`))
+	var postgresErr *pgconn.PgError
+	if !errors.As(err, &postgresErr) || postgresErr.Code != "P0001" || tx.rollbacks != 1 {
+		t.Fatalf("err=%v postgres=%#v rollbacks=%d", err, postgresErr, tx.rollbacks)
+	}
+}
+
+func TestChargeAndActivateCreationPreservesDeferredActivationError(t *testing.T) {
+	now := time.Now()
+	deferred := &pgconn.PgError{Code: "40001", Message: "could not serialize access"}
+	tx := &generationStateTransaction{results: []*jobRows{
+		{rows: [][]any{{"ledger-1", int64(1), int64(1), int64(1), int64(1), now, now, int64(-1)}}},
+		{err: deferred},
+	}}
+	db := NewDatabase(Config{Backend: BackendPostgres}, &generationStatePool{tx: tx})
+
+	_, err := db.ChargeAndActivateCreation(context.Background(), billing.ChargeRequest{OrganizationID: "org", JobID: "job", AmountFen: 1}, json.RawMessage(`{"status":"pending"}`))
+	var postgresErr *pgconn.PgError
+	if !errors.As(err, &postgresErr) || postgresErr.Code != "40001" || tx.rollbacks != 1 {
+		t.Fatalf("err=%v postgres=%#v rollbacks=%d", err, postgresErr, tx.rollbacks)
+	}
+}
+
 func TestChargeAndActivateCreationTreatsCommittedButLostResponseAsSuccess(t *testing.T) {
 	now := time.Date(2026, 8, 13, 8, 0, 0, 0, time.UTC)
 	charged := json.RawMessage(`{"status":"charged","amountFen":35,"ledgerEntryId":"ledger-1"}`)