Modernize the gradle setup a little more.

android/build.gradle.kts

@@ -4,7 +4,6 @@ import java.io.ByteArrayOutputStream
 
 plugins {
 	id("com.android.application")
-	id("org.jetbrains.kotlin.android")
 	id("com.google.protobuf")
 }
 
@@ -149,6 +148,8 @@ android {
 			isMinifyEnabled = false
 			if (project.hasProperty("RELEASE_STORE_FILE")) {
 				signingConfig = signingConfigs.getByName("release")
+			} else {
+				println("WARNING: RELEASE_STORE_FILE is missing. Release builds will be unusable.")
 			}
 		}
 	}

build.gradle.kts

@@ -1,5 +1,4 @@
 plugins {
 	id("com.android.application") version "9.0.0" apply false
-	id("org.jetbrains.kotlin.android") version "2.2.21" apply false
-	id("com.google.protobuf") version "0.9.5" apply false
+	id("com.google.protobuf") version "0.9.6" apply false
 }

gradle.properties

@@ -12,5 +12,4 @@ android.uniquePackageNames=false
 android.dependency.useConstraints=true
 android.r8.strictFullModeForKeepRules=false
 android.r8.optimizedResourceShrinking=false
-android.builtInKotlin=false
 android.newDsl=false