[flutter_template_images] Add macOS app icon assets (#1930)

Adds the the AppIcon assets in the macOS app template while
simultaneously updating them to meet Apple's icon guidelines as of macOS
Big Sur.

Ref: https://developer.apple.com/design/human-interface-guidelines/macos/icons-and-images/app-icon/

Issue: https://github.com/flutter/flutter/issues/103371
diff --git a/packages/flutter_template_images/CHANGELOG.md b/packages/flutter_template_images/CHANGELOG.md
index 4d07481..b4ca5d6 100644
--- a/packages/flutter_template_images/CHANGELOG.md
+++ b/packages/flutter_template_images/CHANGELOG.md
@@ -1,6 +1,7 @@
-## NEXT
+## 4.1.0
 
 * Updates package description.
+* Adds macOS template app icons, updated to Big Sur style.
 
 ## 4.0.0
 
diff --git a/packages/flutter_template_images/pubspec.yaml b/packages/flutter_template_images/pubspec.yaml
index aa32524..b163690 100644
--- a/packages/flutter_template_images/pubspec.yaml
+++ b/packages/flutter_template_images/pubspec.yaml
@@ -2,7 +2,7 @@
 description: Image files for use in flutter_tools templates without adding binary files to flutter/flutter.
 repository: https://github.com/flutter/packages/tree/main/packages/flutter_template_images
 issue_tracker: https://github.com/flutter/flutter/issues?q=is%3Aissue+is%3Aopen+label%3A%22p%3A+flutter_template_images%22
-version: 4.0.0
+version: 4.1.0
 
 environment:
   sdk: ">=2.1.0 <3.0.0"
diff --git a/packages/flutter_template_images/templates/app_shared/macos.tmpl/Runner/Assets.xcassets/AppIcon.appiconset/app_icon_1024.png b/packages/flutter_template_images/templates/app_shared/macos.tmpl/Runner/Assets.xcassets/AppIcon.appiconset/app_icon_1024.png
new file mode 100644
index 0000000..82b6f9d
--- /dev/null
+++ b/packages/flutter_template_images/templates/app_shared/macos.tmpl/Runner/Assets.xcassets/AppIcon.appiconset/app_icon_1024.png
Binary files differ
diff --git a/packages/flutter_template_images/templates/app_shared/macos.tmpl/Runner/Assets.xcassets/AppIcon.appiconset/app_icon_128.png b/packages/flutter_template_images/templates/app_shared/macos.tmpl/Runner/Assets.xcassets/AppIcon.appiconset/app_icon_128.png
new file mode 100644
index 0000000..13b35eb
--- /dev/null
+++ b/packages/flutter_template_images/templates/app_shared/macos.tmpl/Runner/Assets.xcassets/AppIcon.appiconset/app_icon_128.png
Binary files differ
diff --git a/packages/flutter_template_images/templates/app_shared/macos.tmpl/Runner/Assets.xcassets/AppIcon.appiconset/app_icon_16.png b/packages/flutter_template_images/templates/app_shared/macos.tmpl/Runner/Assets.xcassets/AppIcon.appiconset/app_icon_16.png
new file mode 100644
index 0000000..0a3f5fa
--- /dev/null
+++ b/packages/flutter_template_images/templates/app_shared/macos.tmpl/Runner/Assets.xcassets/AppIcon.appiconset/app_icon_16.png
Binary files differ
diff --git a/packages/flutter_template_images/templates/app_shared/macos.tmpl/Runner/Assets.xcassets/AppIcon.appiconset/app_icon_256.png b/packages/flutter_template_images/templates/app_shared/macos.tmpl/Runner/Assets.xcassets/AppIcon.appiconset/app_icon_256.png
new file mode 100644
index 0000000..bdb5722
--- /dev/null
+++ b/packages/flutter_template_images/templates/app_shared/macos.tmpl/Runner/Assets.xcassets/AppIcon.appiconset/app_icon_256.png
Binary files differ
diff --git a/packages/flutter_template_images/templates/app_shared/macos.tmpl/Runner/Assets.xcassets/AppIcon.appiconset/app_icon_32.png b/packages/flutter_template_images/templates/app_shared/macos.tmpl/Runner/Assets.xcassets/AppIcon.appiconset/app_icon_32.png
new file mode 100644
index 0000000..f083318
--- /dev/null
+++ b/packages/flutter_template_images/templates/app_shared/macos.tmpl/Runner/Assets.xcassets/AppIcon.appiconset/app_icon_32.png
Binary files differ
diff --git a/packages/flutter_template_images/templates/app_shared/macos.tmpl/Runner/Assets.xcassets/AppIcon.appiconset/app_icon_512.png b/packages/flutter_template_images/templates/app_shared/macos.tmpl/Runner/Assets.xcassets/AppIcon.appiconset/app_icon_512.png
new file mode 100644
index 0000000..326c0e7
--- /dev/null
+++ b/packages/flutter_template_images/templates/app_shared/macos.tmpl/Runner/Assets.xcassets/AppIcon.appiconset/app_icon_512.png
Binary files differ
diff --git a/packages/flutter_template_images/templates/app_shared/macos.tmpl/Runner/Assets.xcassets/AppIcon.appiconset/app_icon_64.png b/packages/flutter_template_images/templates/app_shared/macos.tmpl/Runner/Assets.xcassets/AppIcon.appiconset/app_icon_64.png
new file mode 100644
index 0000000..2f1632c
--- /dev/null
+++ b/packages/flutter_template_images/templates/app_shared/macos.tmpl/Runner/Assets.xcassets/AppIcon.appiconset/app_icon_64.png
Binary files differ