Update Android build to Gradle 8.10.2 and Kotlin 2.0.20

Upgraded Gradle wrapper to 8.10.2 and updated Android Gradle plugin to 8.6.1. Migrated Kotlin plugin to org.jetbrains.kotlin.android version 2.0.20 and set Java compatibility to 11. Removed legacy buildscript block for Kotlin in build.gradle for improved build configuration.

{{cookiecutter.out_dir}}/android/app/build.gradle

@@ -1,6 +1,6 @@
 plugins {
     id "com.android.application"
-    id "kotlin-android"
+    id "org.jetbrains.kotlin.android"
     id "dev.flutter.flutter-gradle-plugin"
 }
 
@@ -37,12 +37,12 @@ android {
     }
     
     compileOptions {
-        sourceCompatibility JavaVersion.VERSION_1_8
-        targetCompatibility JavaVersion.VERSION_1_8
+        sourceCompatibility JavaVersion.VERSION_11
+        targetCompatibility JavaVersion.VERSION_11
     }
 
     kotlinOptions {
-        jvmTarget = '1.8'
+        jvmTarget = '11'
     }
 
     sourceSets {
@@ -102,4 +102,4 @@ flutter {
     source '../..'
 }
 
-dependencies {}
+dependencies {}

{{cookiecutter.out_dir}}/android/build.gradle

@@ -1,15 +1,3 @@
-buildscript {
-    ext.kotlin_version = '1.9.24'
-    repositories {
-        google()
-        mavenCentral()
-    }
-
-    dependencies {
-        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
-    }
-}
-
 allprojects {
     repositories {
         google()
@@ -27,4 +15,4 @@ subprojects {
 
 tasks.register("clean", Delete) {
     delete rootProject.buildDir
-}
+}

{{cookiecutter.out_dir}}/android/gradle/wrapper/gradle-wrapper.properties

@@ -2,4 +2,4 @@ distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-8.7-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.10.2-bin.zip

{{cookiecutter.out_dir}}/android/settings.gradle

@@ -23,7 +23,8 @@ pluginManagement {
 
 plugins {
     id "dev.flutter.flutter-plugin-loader" version "1.0.0"
-    id "com.android.application" version "8.3.1" apply false
+    id "com.android.application" version "8.6.1" apply false
+    id "org.jetbrains.kotlin.android" version "2.0.20" apply false
 }
 
-include ":app"
+include ":app"