Xcode 27: compila sin warnings y migra API deprecadas de SwiftUI

- Imports de CoreData que faltaban (MemberImportVisibility) en AccountsView,
  ImportDataView, ChartsContainerView y AddSourceView.
- Aislamiento MainActor: IsolatedDefaultValues en el target de la app,
  LinearGradient @MainActor, WatchSyncMessage nonisolated, closures de
  ReviewPromptService/MonthlyCheckInStore/AppIntents.
- Warnings de valores sin usar (SnapshotGapDetector, DashboardLayoutStore,
  OnboardingView, GoalEditorView, CoreDataStack, SettingsViewModel).
- foregroundColor→foregroundStyle, cornerRadius→clipShape,
  navigationBarLeading/Trailing→topBarLeading/Trailing,
  Task.sleep(nanoseconds:)→sleep(for:), NavigationLink(isActive:)→
  navigationDestination(isPresented:).

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01F1u4K16xy7eQVtgsYNZ9Vn

PortfolioJournal/Views/Dashboard/QuickUpdateView.swift

@@ -91,7 +91,7 @@ struct QuickUpdateView: View {
                                         Image(systemName: "arrow.down.circle.fill")
                                     }
                                     .font(.subheadline.weight(.semibold))
-                                    .foregroundColor(.white)
+                                    .foregroundStyle(.white)
                                     .padding(.vertical, 2)
                                 }
                                 .listRowBackground(Color.appPrimary)
@@ -243,14 +243,14 @@ struct QuickUpdateView: View {
                                 .padding(.horizontal, 6)
                                 .padding(.vertical, 1)
                                 .background(Color.appSecondary.opacity(0.15))
-                                .foregroundColor(.appSecondary)
+                                .foregroundStyle(Color.appSecondary)
                                 .clipShape(Capsule())
                         }
                     }
                     if source.latestValue != .zero {
                         Text(source.latestValue.currencyString)
                             .font(.caption)
-                            .foregroundColor(.secondary)
+                            .foregroundStyle(.secondary)
                     }
                 }
                 Spacer()
@@ -269,7 +269,7 @@ struct QuickUpdateView: View {
                 HStack {
                     Text(String(localized: "quick_update_contribution_label"))
                         .font(.caption)
-                        .foregroundColor(.secondary)
+                        .foregroundStyle(.secondary)
                     Spacer()
                     TextField(
                         String(localized: "quick_update_contribution_placeholder"),
@@ -279,7 +279,7 @@ struct QuickUpdateView: View {
                     .multilineTextAlignment(.trailing)
                     .frame(width: 120)
                     .font(.caption)
-                    .foregroundColor(.secondary)
+                    .foregroundStyle(.secondary)
                 }
             }
         }