Change the handling of login errors.

Previously FlashMessage was used to provide an error message during login.
This PR changes that flow to not use redirect for this, but renders the HTML and responds using the correct status code where needed. This should solve some issues which were reported in the past.

Thanks to @RealOrangeOne, for initiating this with a PR.

Fixes #2448
Fixes #2712
Closes #2715

Co-authored-by: Jake Howard <git@theorangeone.net>

src/static/templates/admin/organizations.hbs

@@ -49,7 +49,7 @@
 </main>
 
 <link rel="stylesheet" href="{{urlpath}}/vw_static/datatables.css" />
-<script src="{{urlpath}}/vw_static/jquery-3.6.0.slim.js"></script>
+<script src="{{urlpath}}/vw_static/jquery-3.6.1.slim.js"></script>
 <script src="{{urlpath}}/vw_static/datatables.js"></script>
 <script>
     'use strict';

src/static/templates/admin/users.hbs

@@ -136,7 +136,7 @@
 </main>
 
 <link rel="stylesheet" href="{{urlpath}}/vw_static/datatables.css" />
-<script src="{{urlpath}}/vw_static/jquery-3.6.0.slim.js"></script>
+<script src="{{urlpath}}/vw_static/jquery-3.6.1.slim.js"></script>
 <script src="{{urlpath}}/vw_static/datatables.js"></script>
 <script>
     'use strict';