Unify login via popup on home. No need for separate login html page.

Delete old login html page. Login via popup on home is the single,
unified login experience.

Have docs mention khoj home url, no need to mention /login as login
popup shows on home page too

documentation/docusaurus.config.js

@@ -103,7 +103,7 @@ const config = {
             'aria-label': 'GitHub repository',
           },
           {
-            href: 'https://app.khoj.dev/login',
+            href: 'https://app.khoj.dev',
             position: 'right',
             className: 'header-cloud-link',
             title: 'Khoj Cloud',
@@ -191,14 +191,14 @@ const config = {
               },
               {
                 label: 'Khoj Cloud',
-                href: 'https://app.khoj.dev/login',
+                href: 'https://app.khoj.dev',
               },
               {
                 label: 'GitHub',
                 href: 'https://github.com/khoj-ai/khoj',
               },
               {
-                label: 'Website',
+                label: 'Khoj Inc.',
                 href: 'https://khoj.dev',
               },
             ],