iOS: one-line mixer faders so every stem fits; wide now-playing layout and landscape for iPhone Duo

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

ios/project.yml

@@ -32,7 +32,7 @@ targets:
         CFBundleVersion: $(CURRENT_PROJECT_VERSION)
         UILaunchScreen: {}
         UIBackgroundModes: [audio, fetch]
-        UISupportedInterfaceOrientations: [UIInterfaceOrientationPortrait]
+        UISupportedInterfaceOrientations: [UIInterfaceOrientationPortrait, UIInterfaceOrientationLandscapeLeft, UIInterfaceOrientationLandscapeRight]
         CADisableMinimumFrameDurationOnPhone: true
         ITSAppUsesNonExemptEncryption: false
         NSLocalNetworkUsageDescription: Stemify talks to Plex and the stems server on your home network.