Add Foundry mobile layout with Tauri iOS/Android support

- Add responsive mobile layout with bottom pill tab bar, swipe navigation, and task list as home screen
- Add platform detection (useIsMobile hook) with viewport breakpoint and VITE_MOBILE build flag
- Mobile-optimize settings/billing/account pages (single-column layout with horizontal tabs)
- Add iOS safe area inset handling with 47px minimum padding
- Scaffold Tauri v2 mobile targets (iOS/Android) with platform-gated sidecar and capabilities
- Add notification sound support and mobile build script

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

foundry/packages/desktop/src-tauri/gen/apple/Podfile

@@ -0,0 +1,21 @@
+# Uncomment the next line to define a global platform for your project
+
+target 'foundry_iOS' do
+platform :ios, '14.0'
+  # Pods for foundry_iOS
+end
+
+target 'foundry_macOS' do
+platform :osx, '11.0'
+  # Pods for foundry_macOS
+end
+
+# Delete the deployment target for iOS and macOS, causing it to be inherited from the Podfile
+post_install do |installer|
+ installer.pods_project.targets.each do |target|
+  target.build_configurations.each do |config|
+   config.build_settings.delete 'IPHONEOS_DEPLOYMENT_TARGET'
+   config.build_settings.delete 'MACOSX_DEPLOYMENT_TARGET'
+  end
+ end
+end