Added support for 3rd party dependencies in plugins (#434)

plugins/igdb/build.gradle.kts

@@ -4,4 +4,22 @@ plugins {
 
 dependencies {
     ksp("care.better.pf4j:pf4j-kotlin-symbol-processing:2.0.20-1.0.1")
+
+    // IGDB API client
+    implementation("io.github.husnjak:igdb-api-jvm:1.2.0")
+}
+
+tasks.register<Copy>("copyDependencyClasses") {
+    dependsOn(tasks.jar)
+
+    duplicatesStrategy = DuplicatesStrategy.EXCLUDE
+
+    from(configurations.runtimeClasspath.get().map { project.zipTree(it) }) {
+        include("**/*.class")
+    }
+    into(layout.buildDirectory.get().asFile.resolve("classes/kotlin/main"))
+}
+
+tasks.build {
+    dependsOn("copyDependencyClasses")
 }