[build] Restructure to composite build

conventions/src/main/kotlin/de.siphalor.tweed5.expanded-sources-jar.gradle.kts

@@ -0,0 +1,34 @@
+import io.freefair.gradle.plugins.lombok.tasks.Delombok
+
+plugins {
+	java
+	`java-library`
+	alias(libs.plugins.lombok)
+}
+
+val expandedSourcesElements = configurations.consumable("expandedSourcesElements") {
+	extendsFrom(configurations.implementation.get())
+	attributes {
+		attribute(Category.CATEGORY_ATTRIBUTE, objects.named(Category.DOCUMENTATION))
+		attribute(DocsType.DOCS_TYPE_ATTRIBUTE, objects.named(DocsType.SOURCES))
+		attribute(Bundling.BUNDLING_ATTRIBUTE, objects.named(Bundling.EXTERNAL))
+	}
+}
+
+val delombok = tasks.getByName<Delombok>("delombok")
+
+val sourcesJar by tasks.registering(Jar::class) {
+	group = LifecycleBasePlugin.BUILD_GROUP
+
+	dependsOn(delombok)
+	from(delombok.target)
+	archiveClassifier.set("sources")
+}
+artifacts.add(expandedSourcesElements.name, sourcesJar)
+
+tasks.named("build") { dependsOn(sourcesJar) }
+
+components.named<AdhocComponentWithVariants>("java") {
+	addVariantsFromConfiguration(expandedSourcesElements.get()) {}
+}
+