Fix iOS app icon and extension bundle version validation

Declare XSAppIconAssets in the app manifest so actool receives --app-icon
and the bundle carries CFBundleIconName, and always pass both Xcode version
placeholders to the ReplayKit extension so an empty build number cannot
drop CFBundleVersion and fail installd.

clients/apple/VoiceCat.iOS/Info.plist

@@ -3,6 +3,7 @@
 <plist version="1.0"><dict>
   <key>CFBundleDisplayName</key><string>VoiceCat</string>
   <key>CFBundleIdentifier</key><string>me.iamtalon.voicecat</string>
+  <key>XSAppIconAssets</key><string>Assets.xcassets/AppIcon.appiconset</string>
   <key>LSRequiresIPhoneOS</key><true/>
   <key>NSMicrophoneUsageDescription</key><string>VoiceCat needs microphone access to transmit your voice in channels.</string>
   <key>UIBackgroundModes</key><array><string>audio</string><string>screen-capture</string></array>

clients/apple/VoiceCat.iOS/build-broadcast-extension.sh

@@ -10,10 +10,14 @@ project="$script_dir/../../../native/apple/broadcast/VoiceCatBroadcast.xcodeproj
 
 mkdir -p "$output"
 signing=()
-versioning=(MARKETING_VERSION="${VOICECAT_DISPLAY_VERSION:-0.0.1}")
-if [[ -n "${VOICECAT_BUILD_NUMBER:-}" ]]; then
-  versioning+=(CURRENT_PROJECT_VERSION="$VOICECAT_BUILD_NUMBER")
-fi
+# Both keys must always be set. The extension manifest expands these placeholders, and an
+# empty CURRENT_PROJECT_VERSION drops CFBundleVersion, which installd rejects. The defaults
+# match ApplicationDisplayVersion/ApplicationVersion in VoiceCat.iOS.csproj so that the host
+# and extension versions agree when no release build number is supplied.
+versioning=(
+  MARKETING_VERSION="${VOICECAT_DISPLAY_VERSION:-0.0.1}"
+  CURRENT_PROJECT_VERSION="${VOICECAT_BUILD_NUMBER:-1}"
+)
 if [[ "$sdk" == "iphonesimulator" ]]; then
   signing+=(CODE_SIGNING_ALLOWED=NO)
 elif [[ -n "${VOICECAT_BROADCAST_CODESIGN_KEY:-}" && -n "${VOICECAT_BROADCAST_CODESIGN_PROVISION:-}" ]]; then