docs: Add minimum OS version bump to CHANGELOG (#6757)

Add breaking change entry documenting the bump in minimum OS versions:
- iOS 15.0
- macOS 12.0
- tvOS 15.0
- visionOS 1.0
- watchOS 8.0

Co-authored-by: Cursor Agent <cursoragent@cursor.com>

Author: philipphofmann

CHANGELOG.md

@@ -4,6 +4,7 @@
 
 ### Breaking Changes
 
+- Bumped minimum OS versions to iOS 15.0, macOS 12.0, tvOS 15.0, visionOS 1.0, and watchOS 8.0
 - Moves `SentryEventDecoder` to SPI (#6365)
 - Makes `PreviewRedactOptions`, `SentryProfileOptions`, `SentryRedactViewHelper`, `SentryViewScreenshotOptions`, `SentryReplayOptions`, `SentryUserFeedbackConfiguration`, `SentryUserFeedbackFormConfiguration`, `SentryUserFeedbackThemeConfiguration`, `SentryUserFeedbackWidgetConfiguration`, `SentryFeedback`, and `SentryExperimentalOptions` `final` (#6365)
 - Removes Decodable conformances from the public API of model classes (#5691)