feat: add paper plugin

paper/build.gradle.kts

@@ -0,0 +1,35 @@
+plugins {
+    `java-library`
+
+    id("com.gradleup.shadow") version "9.3.0"
+    id("xyz.jpenilla.run-paper") version "3.0.2"
+}
+
+repositories {
+    mavenCentral()
+    maven("https://repo.papermc.io/repository/maven-public/")
+}
+
+dependencies {
+    implementation(libs.guava)
+    implementation(project(":common"))
+
+    compileOnly("io.papermc.paper:paper-api:1.21.10-R0.1-SNAPSHOT")
+}
+
+java {
+    toolchain.languageVersion.set(JavaLanguageVersion.of(21))
+}
+
+tasks {
+    runServer {
+        // Configure the Minecraft version for our task.
+        // This is the only required configuration besides applying the plugin.
+        // Your plugin's jar (or shadowJar if present) will be used automatically.
+        minecraftVersion("1.21.10")
+    }
+
+    withType<Jar> {
+        from("src/main/resources")
+    }
+}