Fix macOS build error and iPhone 16 display issues

- Split multi-platform target into separate iOS and macOS targets to prevent iOS share extension from being embedded in macOS build
- Add launch screen configuration and full screen support for proper iPhone 16 display
- Configure iOS-specific Info.plist entries for background modes and interface orientations

bitchat/Info.plist

@@ -18,6 +18,15 @@
 	<string>APPL</string>
 	<key>CFBundleShortVersionString</key>
 	<string>$(MARKETING_VERSION)</string>
+	<key>CFBundleURLTypes</key>
+	<array>
+		<dict>
+			<key>CFBundleURLSchemes</key>
+			<array>
+				<string>bitchat</string>
+			</array>
+		</dict>
+	</array>
 	<key>CFBundleVersion</key>
 	<string>$(CURRENT_PROJECT_VERSION)</string>
 	<key>LSMinimumSystemVersion</key>
@@ -40,14 +49,7 @@
 	<array>
 		<string>UIInterfaceOrientationPortrait</string>
 	</array>
-	<key>CFBundleURLTypes</key>
-	<array>
-		<dict>
-			<key>CFBundleURLSchemes</key>
-			<array>
-				<string>bitchat</string>
-			</array>
-		</dict>
-	</array>
+	<key>UIRequiresFullScreen</key>
+	<true/>
 </dict>
 </plist>