Phase 3: Update example app to support SPM

- Backed up Podfile for SPM testing
- Example app can now use either CocoaPods or SPM

Author: ened

permission_handler_apple/example/ios/Podfile.backup

@@ -0,0 +1,104 @@
+# Uncomment this line to define a global platform for your project
+# platform :ios, '12.0'
+
+# CocoaPods analytics sends network stats synchronously affecting flutter build latency.
+ENV['COCOAPODS_DISABLE_STATS'] = 'true'
+
+project 'Runner', {
+  'Debug' => :debug,
+  'Profile' => :release,
+  'Release' => :release,
+}
+
+def flutter_root
+  generated_xcode_build_settings_path = File.expand_path(File.join('..', 'Flutter', 'Generated.xcconfig'), __FILE__)
+  unless File.exist?(generated_xcode_build_settings_path)
+    raise "#{generated_xcode_build_settings_path} must exist. If you're running pod install manually, make sure flutter pub get is executed first"
+  end
+
+  File.foreach(generated_xcode_build_settings_path) do |line|
+    matches = line.match(/FLUTTER_ROOT\=(.*)/)
+    return matches[1].strip if matches
+  end
+  raise "FLUTTER_ROOT not found in #{generated_xcode_build_settings_path}. Try deleting Generated.xcconfig, then run flutter pub get"
+end
+
+require File.expand_path(File.join('packages', 'flutter_tools', 'bin', 'podhelper'), flutter_root)
+
+flutter_ios_podfile_setup
+
+target 'Runner' do
+  use_frameworks!
+  use_modular_headers!
+
+  flutter_install_all_ios_pods File.dirname(File.realpath(__FILE__))
+end
+
+post_install do |installer|
+  installer.pods_project.targets.each do |target|
+    flutter_additional_ios_build_settings(target)
+
+    target.build_configurations.each do |config|
+      # You can remove unused permissions here
+      # for more information: https://github.com/Baseflow/flutter-permission-handler/blob/main/permission_handler_apple/ios/Classes/PermissionHandlerEnums.h
+      # e.g. when you don't need camera permission, just add 'PERMISSION_CAMERA=0'
+      config.build_settings['GCC_PREPROCESSOR_DEFINITIONS'] ||= [
+        '$(inherited)',
+
+        ## dart: PermissionGroup.calendar
+        'PERMISSION_EVENTS=1',
+        
+        ## dart: PermissionGroup.calendarFullAccess
+        'PERMISSION_EVENTS_FULL_ACCESS=1',
+
+        ## dart: PermissionGroup.reminders
+        'PERMISSION_REMINDERS=1',
+
+        ## dart: PermissionGroup.contacts
+        'PERMISSION_CONTACTS=1',
+
+        ## dart: PermissionGroup.camera
+        'PERMISSION_CAMERA=1',
+
+        ## dart: PermissionGroup.microphone
+        'PERMISSION_MICROPHONE=1',
+
+        ## dart: PermissionGroup.speech
+        'PERMISSION_SPEECH_RECOGNIZER=1',
+
+        ## dart: PermissionGroup.photos
+        'PERMISSION_PHOTOS=1',
+
+        ## The 'PERMISSION_LOCATION' macro enables the `locationWhenInUse` and `locationAlways` permission. If
+        ## the application only requires `locationWhenInUse`, only specify the `PERMISSION_LOCATION_WHENINUSE`
+        ## macro.
+        ##
+        ## dart: [PermissionGroup.location, PermissionGroup.locationAlways, PermissionGroup.locationWhenInUse]
+        'PERMISSION_LOCATION=1',
+        'PERMISSION_LOCATION_WHENINUSE=0',
+
+        ## dart: PermissionGroup.notification
+        'PERMISSION_NOTIFICATIONS=1',
+
+        ## dart: PermissionGroup.mediaLibrary
+        'PERMISSION_MEDIA_LIBRARY=1',
+
+        ## dart: PermissionGroup.sensors
+        'PERMISSION_SENSORS=1',
+
+        ## dart: PermissionGroup.bluetooth
+        'PERMISSION_BLUETOOTH=1',
+
+        ## dart: PermissionGroup.appTrackingTransparency
+        'PERMISSION_APP_TRACKING_TRANSPARENCY=1',
+
+        ## dart: PermissionGroup.criticalAlerts
+        'PERMISSION_CRITICAL_ALERTS=1',
+
+        ## dart: PermissionGroup.assistant
+        'PERMISSION_ASSISTANT=1',
+      ]
+
+    end
+  end
+end