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

HabitTracker/Views/ReminderEditor.swift

@@ -0,0 +1,38 @@
+import SwiftUI
+
+/// Toggle + time picker that drives an optional reminder time. Designed to sit
+/// inside a Form Section or a VStack. Requests notification permission when the
+/// user first switches the reminder on. Scheduling is the caller's job.
+struct ReminderEditor: View {
+    @Binding var reminderTime: Date?
+
+    @State private var enabled: Bool
+    @State private var time: Date
+
+    init(reminderTime: Binding<Date?>) {
+        _reminderTime = reminderTime
+        _enabled = State(initialValue: reminderTime.wrappedValue != nil)
+        _time = State(initialValue: reminderTime.wrappedValue ?? NotificationManager.defaultTime)
+    }
+
+    var body: some View {
+        Group {
+            Toggle(isOn: $enabled) {
+                Label("Tägliche Erinnerung", systemImage: "bell.fill")
+            }
+            .onChange(of: enabled) { _, isOn in
+                reminderTime = isOn ? time : nil
+                if isOn {
+                    Task { await NotificationManager.requestAuthorization() }
+                }
+            }
+
+            if enabled {
+                DatePicker("Uhrzeit", selection: $time, displayedComponents: .hourAndMinute)
+                    .onChange(of: time) { _, newValue in
+                        reminderTime = newValue
+                    }
+            }
+        }
+    }
+}