Add new authentication system

src/main/java/emu/grasscutter/auth/DefaultAuthentication.java

@@ -0,0 +1,40 @@
+package emu.grasscutter.auth;
+
+import emu.grasscutter.auth.DefaultAuthenticators.*;
+import emu.grasscutter.server.http.objects.ComboTokenResJson;
+import emu.grasscutter.server.http.objects.LoginResultJson;
+
+/**
+ * The default Grasscutter authentication implementation.
+ * Allows all users to access any account.
+ */
+public final class DefaultAuthentication implements AuthenticationSystem {
+    private final Authenticator<LoginResultJson> passwordAuthenticator = new PasswordAuthenticator();
+    private final Authenticator<LoginResultJson> tokenAuthenticator = new TokenAuthenticator();
+    private final Authenticator<ComboTokenResJson> sessionKeyAuthenticator = new SessionKeyAuthenticator();
+    
+    @Override
+    public void createAccount(String username, String password) {
+        // Unhandled. The default authenticator doesn't store passwords.
+    }
+
+    @Override
+    public void resetPassword(String username) {
+        // Unhandled. The default authenticator doesn't store passwords.
+    }
+
+    @Override
+    public Authenticator<LoginResultJson> getPasswordAuthenticator() {
+        return this.passwordAuthenticator;
+    }
+
+    @Override
+    public Authenticator<LoginResultJson> getTokenAuthenticator() {
+        return this.tokenAuthenticator;
+    }
+
+    @Override
+    public Authenticator<ComboTokenResJson> getSessionKeyAuthenticator() {
+        return this.sessionKeyAuthenticator;
+    }
+}