feat: Kisani UI overhaul — brand identity, gallery, visual polish

- Rename app to Kisani (CFBundleDisplayName, xcodeproj → Kisani.xcodeproj)
- BackupView: kisani. wordmark + SwiftUI-drawn server logo mark (no asset,
  adaptive ink/bg), 206pt progress ring with active-state glow, 4-page
  swipeable ring (progress/pending/failed/uploaded), 4-metric stats strip,
  friendly NAS card (Home Server label), hamburger → AppMenuView sheet
- GalleryView: new NAS + local photo grid with source picker chip, 3-col
  lazy grid, ThumbnailCache, sync-status dots (green = backed up)
- MainTabView: Browse tab → Gallery tab; tab bar uses ultraThinMaterial
  blur background (systemGray3 icons, 9.5pt labels)
- All app icon sizes regenerated from 1024pt source via sips
- LANMonitor: nasReachable Bool?, checkNASReachability(host:port:) TCP ping
- project.yml: photo library usage description updated to Kisani branding

Co-Authored-By: Kutesir <kutesir@provoc.ug>
Co-Authored-By: Sentry <sentry@provoc.ug>

App/NASBackupApp.swift

@@ -22,6 +22,7 @@ struct NASBackupApp: App {
 
 struct RootView: View {
     @EnvironmentObject var store: ConnectionStore
+    @EnvironmentObject var lanMonitor: LANMonitor
 
     var body: some View {
         Group {
@@ -40,5 +41,9 @@ struct RootView: View {
         .animation(.spring(response: 0.4, dampingFraction: 0.85), value: store.isSessionActive)
         .animation(.spring(response: 0.4, dampingFraction: 0.85), value: store.savedConnection?.remotePath)
         .animation(.spring(response: 0.4, dampingFraction: 0.85), value: store.onboardingPhotoShown)
+        .task(id: store.isSessionActive) {
+            guard store.isSessionActive, let conn = store.savedConnection else { return }
+            await lanMonitor.checkNASReachability(host: conn.host, port: conn.port)
+        }
     }
 }