chore: project scaffolding and CI

Gradle 9.4 multi-module setup with Kotlin DSL and version catalog.
GitHub Actions builds on push and PR with JDK 25 (Temurin).

gradle/libs.versions.toml

@@ -0,0 +1,25 @@
+[versions]
+kotlin = "2.2.20"
+coroutines = "1.8.1"
+slf4j = "2.0.13"
+junit = "5.10.2"
+kotest = "5.9.1"
+mockk = "1.13.12"
+shadow = "9.3.1"
+hytaleServer = "2026.03.26-89796e57b"
+
+[libraries]
+kotlinx-coroutines-core = { module = "org.jetbrains.kotlinx:kotlinx-coroutines-core", version.ref = "coroutines" }
+kotlinx-coroutines-jdk8 = { module = "org.jetbrains.kotlinx:kotlinx-coroutines-jdk8", version.ref = "coroutines" }
+kotlinx-coroutines-test = { module = "org.jetbrains.kotlinx:kotlinx-coroutines-test", version.ref = "coroutines" }
+slf4j-api = { module = "org.slf4j:slf4j-api", version.ref = "slf4j" }
+hytale-server = { module = "com.hypixel.hytale:Server", version.ref = "hytaleServer" }
+junit-jupiter = { module = "org.junit.jupiter:junit-jupiter", version.ref = "junit" }
+junit-platform-launcher = { module = "org.junit.platform:junit-platform-launcher", version = "1.10.2" }
+kotest-assertions = { module = "io.kotest:kotest-assertions-core", version.ref = "kotest" }
+mockk = { module = "io.mockk:mockk", version.ref = "mockk" }
+slf4j-simple = { module = "org.slf4j:slf4j-simple", version.ref = "slf4j" }
+
+[plugins]
+kotlin-jvm = { id = "org.jetbrains.kotlin.jvm", version.ref = "kotlin" }
+shadow = { id = "com.gradleup.shadow", version.ref = "shadow" }

gradle/wrapper/gradle-wrapper.properties

@@ -0,0 +1,7 @@
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-9.4.1-bin.zip
+networkTimeout=10000
+validateDistributionUrl=true
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists