Fix[init]: unexpectedly preload LWJGL

Migrating token storage to keychain accidentally causes LWJGL to be
preloaded, making Fabric fails to init.
Add JNI library PojavAccountJNI to do the task of sending access token
from keychain to JVM space.

JavaApp/src/main/java/net/kdt/pojavlaunch/value/MinecraftAccount.java

@@ -44,7 +44,7 @@ public class MinecraftAccount
     }
 
     static {
-        System.load(System.getenv("BUNDLE_PATH") + "/PojavLauncher");
+        System.loadLibrary("PojavAccountJNI");
     }
     public static native String getAccessTokenFromKeychain(String xuid);
 }