build(android): Pin AAR minCompileSdk to minSdk

CHANGELOG.md

@@ -2,6 +2,10 @@
 
 ## Unreleased
 
+### Fixes
+
+- Pin the published Sentry Android SDK's AAR metadata `minCompileSdk` to our `minSdk` (`21`) instead of AGP 9's new default of the SDK's own `compileSdk` (`37`), so apps that depend on the SDK aren't forced to raise their `compileSdk` ([#5823](https://github.com/getsentry/sentry-java/pull/5823))
+
 ### Performance
 
 - Reduce the number of SDK threads: `LifecycleWatcher` now schedules the session-end task on the shared timer executor instead of creating a dedicated `java.util.Timer` thread ([#5819](https://github.com/getsentry/sentry-java/pull/5819))

build.gradle.kts

@@ -177,6 +177,13 @@ subprojects {
                     sourceCompatibility = JavaVersion.VERSION_1_8
                     targetCompatibility = JavaVersion.VERSION_1_8
                 }
+
+                // AGP 9 defaults the AAR metadata minCompileSdk to the library's compileSdk,
+                // which would force every consumer onto that compile SDK. Pin it to our minSdk
+                // so consumers remain free to compile against any SDK we support, as before.
+                defaultConfig {
+                    aarMetadata { minCompileSdk = libs.versions.minSdk.get().toInt() }
+                }
             }
         }