Configure Java 25 toolchain

TODO.md

@@ -3,7 +3,7 @@
 |   ID    |  Status  | Title |
 |:-------:|:--------:|:------|
 | MET-001 |   Done   | Initialize Gradle in the project root, add the Gradle wrapper, and create the project build file. |
-| MET-002 |   Ready  | Set Gradle project metadata and configure a Java toolchain compatible with the target modern Paper version. |
+| MET-002 |   Done   | Set Gradle project metadata and configure a Java toolchain compatible with the target modern Paper version. |
 | MET-003 |   Ready  | Configure repositories and compatible PaperMC, WorldEdit, WorldGuard, and other required or optional dependencies; add build plugins such as Shadow only if needed. |
 | MET-004 |   Ready  | Move or verify plugin.yml under src/main/resources, configure Gradle resource processing, and update its Paper api-version, dependencies, commands, permissions, and required fields. |
 | MET-005 |   Ready  | Add JUnit 5 test infrastructure and keep the default Gradle `test` task server-free. Use an in-memory Paper harness such as MockBukkit for Bukkit/Paper behavior and mocks or test doubles for WorldEdit, WorldGuard, and narrow API boundaries where appropriate. |

build.gradle

@@ -6,6 +6,20 @@ plugins {
 group = 'com.majinnaibu.bukkitplugins'
 description = 'Metropolis'
 
+java {
+    toolchain {
+        languageVersion = JavaLanguageVersion.of(25)
+    }
+}
+
+tasks.named('updateDaemonJvm') {
+    languageVersion = JavaLanguageVersion.of(25)
+}
+
+tasks.withType(JavaCompile).configureEach {
+    options.encoding = 'UTF-8'
+}
+
 tasks.named('wrapper') {
     gradleVersion = '9.8.0'
     distributionType = Wrapper.DistributionType.BIN