add authInternal shortcut function (Big thanks @Ionys320)

server/better-auth.ts

@@ -21,7 +21,9 @@ let godKumaHeaders: Headers;
 let godKumaInitSecret: string = "";
 
 /**
- *
+ * Get the singleton instance of better-auth
+ * Mainly used for http and socket.io authentication
+ * @returns The singleton instance of better-auth
  */
 export function auth() {
     if (authInstance) {
@@ -31,6 +33,15 @@ export function auth() {
     return authInstance;
 }
 
+/**
+ * Do staff without any auth
+ * For internal usage only, the api should be a superset of auth().api
+ * @returns Internal adapter of better-auth
+ */
+export async function authInternal() {
+    return (await auth().$context).internalAdapter;
+}
+
 /**
  *
  */