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>

Features/Browse/BrowseView.swift

@@ -78,6 +78,7 @@ struct BrowseView: View {
             }
         }
         .task { await loadItems(path: currentPath) }
+        .refreshable { await loadItems(path: currentPath) }
     }
 
     // MARK: — Sub-views
@@ -190,6 +191,31 @@ struct BrowseView: View {
                         selectedPath = item.path
                     }
                 }
+                .contextMenu {
+                    if item.isDirectory {
+                        Button {
+                            navigate(to: item.path)
+                        } label: {
+                            Label("Open Folder", systemImage: "folder")
+                        }
+                        Button {
+                            selectedPath = item.path
+                        } label: {
+                            Label("Select This Folder", systemImage: "checkmark.circle")
+                        }
+                    } else {
+                        Button {
+                            // Placeholder: Make available offline
+                        } label: {
+                            Label("Make Available Offline", systemImage: "arrow.down.circle")
+                        }
+                    }
+                    Button(role: .destructive) {
+                        // Placeholder: context-sensitive action
+                    } label: {
+                        Label("More Info", systemImage: "info.circle")
+                    }
+                }
                 .listRowInsets(EdgeInsets())
                 .listRowSeparator(.hidden)
                 .listRowBackground(Color.clear)