chore(repo): iOS-App als ios/ ins Hauptrepo uebernehmen

Calendarr-IOS wird mit vollstaendiger Historie als Unterverzeichnis
ios/ eingebunden. Damit liegen Server, Web, Android und iOS in einem
gemeinsamen Repo.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

ios/CalendarrWatch/WatchSnapshotModel.swift

@@ -0,0 +1,52 @@
+import Foundation
+import WidgetKit
+import CalendarrCore
+
+/// What the watch views read. Holds the last received snapshot, the calendar
+/// list, and this watch's filter.
+@MainActor
+@Observable
+final class WatchSnapshotModel {
+    private(set) var result: SnapshotReadResult = .neverWritten
+    private(set) var calendars: [SnapshotCalendar] = []
+    private(set) var hiddenKeys: Set<String> = WatchFilterStore.load()
+
+    private let store = SnapshotStore()
+    private var changeToken: SnapshotChangeNotifier.ObservationToken?
+
+    init() {
+        reload()
+        // The receiver writes through SnapshotStore, which broadcasts. Listening
+        // here means the UI does not have to be notified separately.
+        changeToken = SnapshotChangeNotifier.observe { [weak self] in
+            Task { @MainActor in self?.reload() }
+        }
+    }
+
+    func reload() {
+        result = store.read()
+        calendars = store.readCalendars()
+    }
+
+    /// The snapshot with this watch's filter applied, or nil when there is
+    /// nothing usable to show.
+    var visible: CalendarrSnapshot? {
+        result.snapshot?.filtered(excludingCalendarKeys: hiddenKeys)
+    }
+
+    var language: String { result.snapshot?.language ?? "system" }
+
+    func isHidden(_ key: String) -> Bool { hiddenKeys.contains(key) }
+
+    /// The display name for an event's calendar. Events carry only a
+    /// `calendarKey`; the names travel separately, in the calendar list.
+    func calendarName(for key: String) -> String? {
+        calendars.first { $0.id == key }?.name
+    }
+
+    func setHidden(_ key: String, _ hidden: Bool) {
+        if hidden { hiddenKeys.insert(key) } else { hiddenKeys.remove(key) }
+        WatchFilterStore.save(hiddenKeys)
+        WidgetCenter.shared.reloadAllTimelines()
+    }
+}