Settings sync, calendar visibility sync, event refresh & week-view fixes

- Add two-way settings sync (SettingsSync) with toggle, app-start/foreground/
  10-min pull and debounced push; server wins; view/week-start/dim-past always
  sync. Wire previously-ignored settings (hour height, contrasts, week start,
  default view, dim past) into the actual UI.
- Make AppSettings decoding resilient (decodeIfPresent) so getSettings no longer
  fails on iOS-only fields the server omits; keep text/bg/line colors local-only;
  month divider/label colors now sync.
- Auto-refresh after create/edit (cache-busting) and optimistic removal on
  delete; switch delete confirm to a centered alert. Add HA event deletion.
- Calendar visibility: fix inverted hide/show toggle; normalize calendar keys so
  local filtering works for all sources; sync banish with server sidebar_hidden
  (CalDAV/Google/HA), refetch on un-banish.
- Manual "sync with server" button in the menu.
- Upcoming widget shows next 5 days (renamed).
- Week/Day view: route multi-day timed events to the all-day strip so they no
  longer render as a full-height block.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Calendarr iOS/Views/MenuSheet.swift

@@ -5,6 +5,7 @@ struct MenuSheet: View {
     @Environment(AppState.self) var appState
     @Environment(\.dismiss) var dismiss
     @AppStorage("appLanguage") private var appLang = "system"
+    @State private var isSyncing = false
 
     var body: some View {
         NavigationStack {
@@ -68,6 +69,19 @@ struct MenuSheet: View {
                     }
                 }
 
+                Section(L10n.t("menu.sync.section", appLang)) {
+                    Button {
+                        Task { await syncNow() }
+                    } label: {
+                        HStack {
+                            Label(L10n.t("menu.sync", appLang), systemImage: "arrow.triangle.2.circlepath")
+                            Spacer()
+                            if isSyncing { ProgressView() }
+                        }
+                    }
+                    .disabled(isSyncing)
+                }
+
                 Section {
                     Button(role: .destructive) {
                         dismiss()
@@ -88,4 +102,14 @@ struct MenuSheet: View {
             }
         }
     }
+
+    /// Manual sync: pull appearance/behaviour settings from the server, then
+    /// ask the calendar host to re-fetch events (cache-busting).
+    private func syncNow() async {
+        isSyncing = true
+        await SettingsSync.pull(api: api)
+        NotificationCenter.default.post(name: .manualSyncRequested, object: nil)
+        isSyncing = false
+        dismiss()
+    }
 }