refactor: migrate to agp9

client/build.gradle.kts

@@ -1,15 +1,16 @@
-import org.jetbrains.kotlin.gradle.ExperimentalKotlinGradlePluginApi
 import org.jetbrains.kotlin.gradle.dsl.JvmTarget
 
 plugins {
     alias(libs.plugins.kotlinMultiplatform)
     alias(libs.plugins.kotlinSerialization)
-    alias(libs.plugins.androidLibrary)
+    alias(libs.plugins.androidMultiplatformLibrary)
 }
 
 kotlin {
-    androidTarget {
-        @OptIn(ExperimentalKotlinGradlePluginApi::class)
+    android {
+        namespace = "moe.lava.banksia.client"
+        compileSdk = libs.versions.android.compileSdk.get().toInt()
+
         compilerOptions {
             jvmTarget.set(JvmTarget.JVM_11)
         }
@@ -41,15 +42,3 @@ kotlin {
         }
     }
 }
-
-android {
-    namespace = "moe.lava.banksia.client"
-    compileSdk = libs.versions.android.compileSdk.get().toInt()
-    compileOptions {
-        sourceCompatibility = JavaVersion.VERSION_11
-        targetCompatibility = JavaVersion.VERSION_11
-    }
-    defaultConfig {
-        minSdk = libs.versions.android.minSdk.get().toInt()
-    }
-}