docs: deprecate store.state.auth.user

Author: marshallswain

docs/3.0-major-release.md

@@ -31,11 +31,11 @@ Due to changes in how reactivity is applied to service state (it's now using Vue
 - `user`: returns the reactive, logged-in user from the `userService` specified in the options.
 - `isAuthenticated`: a easy to remember boolean attribute for if the user is logged in.
 
-If you depend on a reactive, logged-in user in your apps, here are the steps to fixing the reactivity:
+If you depend on a reactive, logged-in user in your apps, here is how to fix the reactivity:
 
 - Replace any reference to `store.state.auth.user` with `store.state.getters('auth/user')`.
 
-That's it. :)
+Because the `user` state is no longer reactive, it is logical for it to be removed in the next version.  It will likely be replaced by a `userId` attribute in Feathers-Vuex 4.0.
 
 
 ### Server-Side Pagination Support is Off by Default

docs/auth-plugin.md

@@ -30,7 +30,7 @@ It includes the following state by default:
   userService: null, // Specify the userService to automatically populate the user upon login.
   entityIdField: 'userId', // The property in the payload storing the user id
   responseEntityField: 'user', // The property in the payload storing the user
-  user: null, // automatically populates if you have correctly configured the three previous settings.
+  user: null, // Deprecated: This is no longer reactive, so use the `user` getter. See below.
 
   isAuthenticatePending: false,
   isLogoutPending: false,