bump java to jdk 25, update vscode

.vscode/settings.json

@@ -0,0 +1,3 @@
+{
+    "java.configuration.updateBuildConfiguration": "automatic"
+}

build.gradle

@@ -18,7 +18,7 @@ version = '1.0'
 // Apply a specific Java toolchain to ease working on different environments.
 java {
     toolchain {
-        languageVersion = JavaLanguageVersion.of(24)
+        languageVersion = JavaLanguageVersion.of(25)
     }
 }