refactor: migrate to Kotlin build scripts

build.gradle.kts

@@ -0,0 +1,39 @@
+plugins {
+    kotlin("jvm") version "1.6.20"
+    id("com.github.johnrengelman.shadow") version "7.1.2"
+}
+
+group = "app.revanced"
+version = "1.0"
+
+repositories {
+    mavenCentral()
+    mavenLocal()
+    maven {
+        url = uri("https://maven.pkg.github.com/ReVancedTeam/multidexlib2")
+        credentials {
+            username = project.findProperty("gpr.user") as String? ?: System.getenv("GITHUB_ACTOR") // DO NOT CHANGE!
+            password = project.findProperty("gpr.key")  as String? ?: System.getenv("GITHUB_TOKEN") // DO NOT CHANGE!
+        }
+    }
+}
+
+dependencies {
+    implementation(kotlin("stdlib"))
+
+    implementation("app.revanced:revanced-patcher:1.0.0-dev.8")
+    implementation("app.revanced:revanced-patches:1.0.0-dev.4")
+
+    implementation("com.google.code.gson:gson:2.9.0")
+}
+
+tasks {
+    build {
+        dependsOn(shadowJar)
+    }
+    shadowJar {
+        manifest {
+            attributes(Pair("Main-Class", "app.revanced.cli.MainKt"))
+        }
+    }
+}