Extract UI assets from JAR on first launch

launcher/launcher/src/main/java/sashegdev/zernmc/launcher/ui/jfx/JFXLauncher.java

@@ -14,6 +14,8 @@ import me.sashegdev.zernmc.launcher.minecraft.InstanceManager;
 
 import java.io.InputStream;
 import java.io.OutputStream;
+import java.util.jar.JarEntry;
+import java.util.jar.JarFile;
 import java.net.InetSocketAddress;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
@@ -77,11 +79,46 @@ public class JFXLauncher extends Application {
         launch(args);
     }
 
+    private static void extractAssets() {
+        try {
+            Path assetsDir = Paths.get("assets");
+            if (Files.exists(assetsDir)) {
+                return;
+            }
+            
+            System.out.println("[JFX] Извлечение assets из JAR...");
+            Path jarPath = Paths.get(JFXLauncher.class.getProtectionDomain().getCodeSource().getLocation().toURI());
+            if (Files.exists(jarPath) && jarPath.toString().endsWith(".jar")) {
+                try (JarFile jar = new JarFile(jarPath.toFile())) {
+                    var entries = jar.entries();
+                    while (entries.hasMoreElements()) {
+                        JarEntry entry = entries.nextElement();
+                        if (entry.getName().startsWith("assets/")) {
+                            Path outPath = assetsDir.resolve(entry.getName().substring(7));
+                            if (entry.isDirectory()) {
+                                Files.createDirectories(outPath);
+                            } else {
+                                Files.createDirectories(outPath.getParent());
+                                try (InputStream is = jar.getInputStream(entry)) {
+                                    Files.copy(is, outPath);
+                                }
+                            }
+                        }
+                    }
+                }
+                System.out.println("[JFX] Assets извлечены");
+            }
+        } catch (Exception e) {
+            System.out.println("[JFX] Ошибка извлечения assets: " + e.getMessage());
+        }
+    }
+
     @Override
     public void start(Stage stage) {
         this.mainStage = stage;
 
         try {
+            extractAssets();
             log("Запуск JFX UI...");
             startServer();