Feature variants (#376)

Migrate from buildSrc to build-logic. Setup feature variants.

build-logic/orx-convention/build.gradle.kts

@@ -0,0 +1,24 @@
+plugins {
+    `kotlin-dsl`
+}
+
+val preload: SourceSet by project.sourceSets.creating
+
+repositories {
+    mavenCentral()
+    mavenLocal()
+}
+val libs = extensions.getByType<VersionCatalogsExtension>().named("libs")
+dependencies {
+    implementation(project(":orx-variant-plugin"))
+    implementation(libs.findLibrary("kotlin-gradle-plugin").get())
+    implementation(libs.findLibrary("dokka-gradle-plugin").get())
+    "preloadImplementation"(openrndr.application)
+    "preloadImplementation"(openrndr.orextensions)
+}
+kotlin {
+    compilerOptions {
+        freeCompilerArgs.add("-Xskip-metadata-version-check")
+    }
+}
+tasks.getByName("compileKotlin").dependsOn("compilePreloadKotlin")