chore: scaffold Voice iOS app (Phase 0)

XcodeGen project, SwiftUI iOS 17 target dev.shane.voice, SPM
livekit-client-swift 2.16.0, mic usage + ATS LAN exception in
Info.plist, placeholder conversation screen and Settings with
server URL field.

.xcodebuildmcp/config.yaml

@@ -0,0 +1,7 @@
+schemaVersion: 1
+sessionDefaults:
+  projectPath: /Users/shane/dev/voice-ios/Voice.xcodeproj
+  scheme: Voice_iOS
+  simulatorName: iPhone 17 Pro
+  simulatorId: AFDA137E-1657-428E-BF01-E5CD7989772C
+  simulatorPlatform: iOS Simulator