Unified macOS capitalization.

Author: IVLIVS-III

packages/in_app_purchase/in_app_purchase/CHANGELOG.md

@@ -1,6 +1,6 @@
 ## 3.0.8
 
-* Adds MacOS as a supported platform.
+* Adds macOS as a supported platform.
 * Updates minimum Flutter version to 2.10.
 * Bumps minimum in_app_purchase_android to 0.2.3.
 

packages/in_app_purchase/in_app_purchase/README.md

@@ -3,7 +3,7 @@ A storefront-independent API for purchases in Flutter apps.
 <!-- If this package were in its own repo, we'd put badges here -->
 
 This plugin supports in-app purchases (_IAP_) through an _underlying store_,
-which can be the App Store (on iOS and MacOS) or Google Play (on Android).
+which can be the App Store (on iOS and macOS) or Google Play (on Android).
 
 |             | Android | iOS  | macOS  |
 |-------------|---------|------|--------|