feat: Phase O Windows-native integration + settings search

- Taskbar progress bar: renderer pushes summarizeQueue aggregate over a new
  taskbar:progress channel (App store subscription); setProgressBar normal/error
- System tray (src/main/tray.ts) + minimize-to-tray (Settings.minimizeToTray);
  close hides to tray, isQuitting guards real exits; icon via getAppIconPath()
  (build/icon.ico added to extraResources)
- Jump list: app.setUserTasks "Open AeroFetch" (thumbnail toolbar deferred)
- Settings search: filters the ~11 SettingsView cards live by text match

Overlay badge deferred (needs a drawn NativeImage). typecheck + test (192) +
build all clean. Roadmap: Phase O COMPLETE.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/main/settings.ts

@@ -47,7 +47,8 @@ const DEFAULTS: Settings = {
   defaultTemplateId: null,
   notifyOnComplete: true,
   autoDownloadNew: true,
-  hasCompletedOnboarding: false
+  hasCompletedOnboarding: false,
+  minimizeToTray: false
 }
 
 /** Fixed path for the --download-archive file; not user-configurable. */
@@ -206,6 +207,7 @@ export function setSettings(partial: Partial<Settings>): Settings {
       case 'notifyOnComplete':
       case 'autoDownloadNew':
       case 'hasCompletedOnboarding':
+      case 'minimizeToTray':
         if (typeof value === 'boolean') s.set(key, value)
         break
       case 'ytdlpChannel':