feat: Sync tab, hamburger menu, network status, browse UX

- Replace History tab with Sync tab (file list, NAS status, free-up-space retention)
- Add AppMenuView hamburger sheet (History, Errors, Connection Status, Sync Activity)
- BackupView: Kisani logo chip in toolbar, hamburger menu button, swipeable ring
  pages (progress/pending/failed/uploaded), always-visible compact stats strip
- SettingsView: NETWORK section (SSID, NAS reachability, trusted-network warning,
  refresh button)
- BrowseView: pull-to-refresh, long-press context menu on items
- LANMonitor: nasReachable, nasCheckTime, checkNASReachability(host:port:)
- ConnectionStore: localRetentionDays (0/60/90/365 days)
- Regenerate xcodeproj with xcodegen to include new files

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Shared/Persistence/ConnectionStore.swift

@@ -58,6 +58,11 @@ final class ConnectionStore: ObservableObject {
         didSet { UserDefaults.standard.set(appearanceMode.rawValue, forKey: "appearanceMode") }
     }
 
+    // Local retention: 0 = never delete, 60/90/365 = days after backup
+    @Published var localRetentionDays: Int {
+        didSet { UserDefaults.standard.set(localRetentionDays, forKey: "localRetentionDays") }
+    }
+
     // Cellular & remote access
     @Published var allowCellularBackup: Bool {
         didSet { UserDefaults.standard.set(allowCellularBackup, forKey: "allowCellularBackup") }
@@ -83,6 +88,7 @@ final class ConnectionStore: ObservableObject {
         quietHoursEnd          = UserDefaults.standard.object(forKey: "quietHoursEnd") as? Int ?? 7
         onboardingPhotoShown   = UserDefaults.standard.bool(forKey: "onboardingPhotoShown")
         appearanceMode         = AppearanceMode(rawValue: UserDefaults.standard.string(forKey: "appearanceMode") ?? "") ?? .system
+        localRetentionDays     = UserDefaults.standard.object(forKey: "localRetentionDays") as? Int ?? 0
         allowCellularBackup    = UserDefaults.standard.object(forKey: "allowCellularBackup") as? Bool ?? false
         useTailscaleWhenRemote = UserDefaults.standard.object(forKey: "useTailscaleWhenRemote") as? Bool ?? false
         tailscaleHost          = UserDefaults.standard.string(forKey: "tailscaleHost") ?? ""