Initiales HabitTracker-Projekt: SwiftUI + SwiftData Gewohnheiten-Tracker

Natives iOS-App-Gerüst (Xcode 26, synchronisierte Ordner, iOS 18+).

Features:
- Gewohnheiten anlegen (Name, SF-Symbol, Farbe), heute abhaken, Streaks, Löschen
- Detailansicht mit Monatskalender (Tage nachtragbar) und Statistiken
- Tägliche Erinnerungen via lokale Notifications
- Home-Screen-Widget (klein/mittel) mit App-Group-Datenaustausch

HabitTrackerWidget/HabitTrackerWidget.swift

@@ -0,0 +1,121 @@
+import WidgetKit
+import SwiftUI
+
+struct HabitTimelineEntry: TimelineEntry {
+    let date: Date
+    let snapshot: WidgetSnapshot
+}
+
+struct Provider: TimelineProvider {
+    func placeholder(in context: Context) -> HabitTimelineEntry {
+        HabitTimelineEntry(date: .now, snapshot: .empty)
+    }
+
+    func getSnapshot(in context: Context, completion: @escaping (HabitTimelineEntry) -> Void) {
+        completion(HabitTimelineEntry(date: .now, snapshot: SharedStore.load()))
+    }
+
+    func getTimeline(in context: Context, completion: @escaping (Timeline<HabitTimelineEntry>) -> Void) {
+        let entry = HabitTimelineEntry(date: .now, snapshot: SharedStore.load())
+        // Reset "today" at the next midnight.
+        let nextMidnight = Calendar.current.startOfDay(for: .now.addingTimeInterval(86_400))
+        completion(Timeline(entries: [entry], policy: .after(nextMidnight)))
+    }
+}
+
+struct HabitTrackerWidgetEntryView: View {
+    var entry: Provider.Entry
+    @Environment(\.widgetFamily) private var family
+
+    private var items: [WidgetSnapshot.Item] { entry.snapshot.items }
+    private var doneCount: Int { items.filter(\.isDoneToday).count }
+
+    var body: some View {
+        if items.isEmpty {
+            emptyState
+        } else {
+            switch family {
+            case .systemSmall:
+                smallView
+            default:
+                mediumView
+            }
+        }
+    }
+
+    private var emptyState: some View {
+        VStack(spacing: 6) {
+            Image(systemName: "checklist")
+                .font(.title)
+                .foregroundStyle(.secondary)
+            Text("Keine Gewohnheiten")
+                .font(.caption)
+                .foregroundStyle(.secondary)
+        }
+    }
+
+    private var header: some View {
+        HStack {
+            Text("Heute")
+                .font(.caption.bold())
+                .foregroundStyle(.secondary)
+            Spacer()
+            Text("\(doneCount)/\(items.count)")
+                .font(.caption.bold())
+                .foregroundStyle(.secondary)
+        }
+    }
+
+    private var smallView: some View {
+        VStack(alignment: .leading, spacing: 8) {
+            header
+            Spacer(minLength: 0)
+            Text("\(doneCount)")
+                .font(.system(size: 44, weight: .bold))
+                + Text(" / \(items.count)")
+                .font(.title3.weight(.semibold))
+                .foregroundColor(.secondary)
+            Text(doneCount == items.count ? "Alles erledigt 🎉" : "erledigt")
+                .font(.caption)
+                .foregroundStyle(.secondary)
+        }
+    }
+
+    private var mediumView: some View {
+        VStack(alignment: .leading, spacing: 8) {
+            header
+            ForEach(items.prefix(3)) { item in
+                HStack(spacing: 10) {
+                    Image(systemName: item.symbolName)
+                        .foregroundStyle(Color(hex: item.colorHex))
+                        .frame(width: 22)
+                    Text(item.name)
+                        .font(.subheadline)
+                        .lineLimit(1)
+                    Spacer()
+                    Image(systemName: item.isDoneToday ? "checkmark.circle.fill" : "circle")
+                        .foregroundStyle(item.isDoneToday ? Color(hex: item.colorHex) : .secondary)
+                }
+            }
+            if items.count > 3 {
+                Text("+ \(items.count - 3) weitere")
+                    .font(.caption2)
+                    .foregroundStyle(.secondary)
+            }
+        }
+    }
+}
+
+struct HabitTrackerWidget: Widget {
+    let kind = "HabitTrackerWidget"
+
+    var body: some WidgetConfiguration {
+        StaticConfiguration(kind: kind, provider: Provider()) { entry in
+            HabitTrackerWidgetEntryView(entry: entry)
+                .containerBackground(.fill.tertiary, for: .widget)
+        }
+        .configurationDisplayName("Gewohnheiten")
+        .description("Dein Fortschritt von heute.")
+        .supportedFamilies([.systemSmall, .systemMedium])
+    }
+}

HabitTrackerWidget/HabitTrackerWidgetBundle.swift

@@ -0,0 +1,9 @@
+import WidgetKit
+import SwiftUI
+
+@main
+struct HabitTrackerWidgetBundle: WidgetBundle {
+    var body: some Widget {
+        HabitTrackerWidget()
+    }
+}