feat(constants): add Java to supported languages and include default code snippet

src/constants/editor/languages.ts

@@ -1,8 +1,14 @@
-import { COriginal, CplusplusOriginal, PythonOriginal } from "devicons-react";
+import {
+  COriginal,
+  CplusplusOriginal,
+  JavaOriginal,
+  PythonOriginal,
+} from "devicons-react";
 
 export const SUPPORTED_LANGUAGES = [
   { key: "c", value: "c", label: "C", icon: COriginal },
   { key: "cpp", value: "cpp", label: "C++", icon: CplusplusOriginal },
+  { key: "java", value: "java", label: "Java", icon: JavaOriginal },
   { key: "python", value: "python", label: "Python", icon: PythonOriginal },
 ];
 

src/constants/editor/values.ts

@@ -14,6 +14,14 @@ using namespace std;
 int main() {
     cout << "Hello, World!";
     return 0;
+}`,
+  },
+  {
+    key: "java",
+    value: `public class Main {
+    public static void main(String[] args) {
+        System.out.println("Hello, World!");
+    }
 }`,
   },
   {