migrated to Gradle and Minestom 2026.10.05-26.2

- Maven -> Gradle 9.6.1 (shadow 9.6.1, Java 25), shadow jar is build/libs/limbo.jar
- Minestom from Maven Central (net.minestom:minestom), speaks Minecraft 26.2 natively
- Velocity forwarding via Auth.Velocity; the secret is no longer hardcoded but read from
  forwarding.secret in the working directory or VELOCITY_FORWARDING_SECRET
- time rate via defaultClock().pause() (new clock API)
- slf4j-simple for logging (Minestom no longer ships a logger)
- removed target/ and Maven files from the repository
- uploadLimbo task copies the jar to the limbo server

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

build.gradle

@@ -0,0 +1,40 @@
+plugins {
+    id 'java'
+    id 'application'
+    id 'com.gradleup.shadow' version '9.6.1'
+}
+
+group = 'eu.mhsl.minecraft'
+version = '1.0-SNAPSHOT'
+
+repositories {
+    mavenCentral()
+}
+
+dependencies {
+    implementation 'net.minestom:minestom:2026.10.05-26.2'
+    runtimeOnly 'org.slf4j:slf4j-simple:2.0.20'
+}
+
+java {
+    toolchain.languageVersion = JavaLanguageVersion.of(25)
+}
+
+application {
+    mainClass = 'eu.mhsl.minecraft.endlessjumper.EndlessJumper'
+}
+
+shadowJar {
+    archiveFileName = 'limbo.jar'
+    mergeServiceFiles()
+}
+
+// Hochladen auf den Limbo: ./gradlew uploadLimbo, danach `sudo systemctl restart limbo`
+tasks.register('uploadLimbo') {
+    dependsOn shadowJar
+    doLast {
+        providers.exec {
+            commandLine 'scp', shadowJar.archiveFile.get().asFile.absolutePath, 'minecraft@10.20.9.3:/home/minecraft/limbo/limbo.jar'
+        }.result.get()
+    }
+}