Re-arrange groups and artefacts when publishing (#2899)

* Re-arrange groups and artefacts when publishing

* Publish core jar

api/geyser/build.gradle.kts

@@ -1,3 +1,10 @@
 dependencies {
     api(projects.api)
+}
+
+publishing {
+    publications.named<MavenPublication>("mavenJava") {
+        groupId = rootProject.group as String + ".geyser"
+        artifactId = "api"
+    }
 }

build.gradle.kts

@@ -36,7 +36,6 @@ subprojects {
     val relativePath = projectDir.relativeTo(rootProject.projectDir).path
 
     if (relativePath.contains("api")) {
-        group = rootProject.group as String + ".api"
         plugins.apply("geyser.api-conventions")
     } else {
         group = rootProject.group as String + ".geyser"

core/build.gradle.kts

@@ -77,6 +77,13 @@ dependencies {
     annotationProcessor(projects.ap)
 }
 
+publishing {
+    publications.named<MavenPublication>("mavenJava") {
+        artifact(tasks["jar"])
+        artifact(tasks["sourcesJar"])
+    }
+}
+
 configure<BlossomExtension> {
     val indra = the<IndraGitExtension>()