Tag some internal auth types with @internal tag (#6248)

Author: hsubox76

.changeset/eighty-bobcats-compete.md

@@ -0,0 +1,5 @@
+---
+'@firebase/auth': patch
+---
+
+Add `@internal` tags to fix public typings file.

packages/auth/src/model/id_token.ts

@@ -87,6 +87,9 @@ export const enum IdTokenResponseKind {
   VerifyPassword = 'identitytoolkit#VerifyPasswordResponse'
 }
 
+/**
+ * @internal
+ */
 export interface TaggedWithTokenResponse {
   _tokenResponse?: PhoneOrOauthTokenResponse;
 }

packages/auth/src/model/user.ts

@@ -90,6 +90,9 @@ export interface UserInternal extends User {
   toJSON(): PersistedBlob;
 }
 
+/**
+ * @internal
+ */
 export interface UserCredentialInternal
   extends UserCredential,
     TaggedWithTokenResponse {