WIP: Widget-, Sync- & Event-Editor-Änderungen

Zwischenstand vor den Sharing/Gruppen/Import-Export-Features (gesichert,
damit die neuen Features sauber darauf aufbauen).

Calendarr iOS/Models/CalendarStore.swift

@@ -277,11 +277,13 @@ class CalendarStore {
     }
 
     /// Trigger a full cache reload (e.g. when cache-range setting changes).
+    /// Intentionally keeps `events` intact so the UI stays populated while
+    /// the network fetch runs; `refreshFromCache` will swap in fresh data
+    /// atomically once it arrives.
     func invalidateCache() {
         cachedStart = nil
         cachedEnd = nil
         allCachedEvents = []
-        events = []
     }
 
     private func mergeIntoCache(_ newEvents: [CalEvent], rangeStart: Date, rangeEnd: Date) {

Calendarr iOS/Models/Localization.swift

@@ -213,6 +213,8 @@ private let strings: [String: [String: String]] = [
         "event.reset_color": "Zurücksetzen",
         "event.edit_title": "Termin bearbeiten",
         "event.new_title": "Neuer Termin",
+        "event.copy_title": "Termin kopieren",
+        "event.copy_to": "In Kalender kopieren",
         "event.save": "Sichern",
         "event.add": "Hinzufügen",
 
@@ -472,6 +474,8 @@ private let strings: [String: [String: String]] = [
         "event.reset_color": "Reset",
         "event.edit_title": "Edit event",
         "event.new_title": "New event",
+        "event.copy_title": "Copy event",
+        "event.copy_to": "Copy to calendar",
         "event.save": "Save",
         "event.add": "Add",