feat: add an example in readme

README.md

@@ -1,3 +1,51 @@
 # node-launcher-kit
 
-A node.js library to install and launch minecraft with or without modloaders.
+A node.js library to install and launch minecraft with or without modloaders.
+
+## Example
+
+You can use this code to install and launch minecraft 1.21.11 with offline auth. This will also automatically download fitting java binaries.
+
+```js
+const gameRoot = path.join(import.meta.dirname, "mc");
+
+// install the correct java version for 1.21.11
+const javaManager = new RuntimeManager(path.join(gameRoot, "java"));
+javaManager.on("progress", console.log) // show progress in logs
+const java = await javaManager.use(await getJavaComponent("1.21.11"))
+
+// instance's config
+const instance = new Instance({
+  version: "1.21.11",
+  auth: offlineAuth("player"),
+  paths: {
+    // root is a shared folder by all instances for common game files. reusing the same root makes install faster.
+    root: gameRoot,
+    // instance is where saves, mods and configs are stored, it is per instance.
+    instance: path.join(gameRoot, "instances", "1.21.11")
+  },
+  javaExecutable: java
+});
+
+// show progress and debug info
+instance.on("progress", console.log);
+instance.on("log", (step, msg) => {
+  console.log(`[${step}] ${msg}`)
+})
+
+// install the game
+await instance.install();
+
+// launch the game, if instance.install already runned once before, you can run instance.launch with the same instance's config without rerunning install.
+const p = await instance.launch();
+
+// show minecraft's logs
+p.stdout.on("data", (d: Buffer) => {
+  console.log(d.toString());
+});
+p.stderr.on("data", (d: Buffer) => {
+  console.log(d.toString());
+});
+```
+
+> You can look in the tests folder to see more examples showing how to use nlk with fabric, forge, neoforge, and modrinth's modpacks.