Update UI design across multiple pages and components

Several changes have been made to improve the user interface and enhance the user experience. This includes redesigning Auth buttons, modifying website layouts and routing, tweaking heading and text sizes for clarity, and revamping the marketing, documentation, and pricing pages. These changes collectively contribute to a cleaner, more concise and navigable interface.

apps/web/app/(marketing)/_components/site-header-account-section.tsx

@@ -10,6 +10,7 @@ import { PersonalAccountDropdown } from '@kit/accounts/personal-account-dropdown
 import { useSignOut } from '@kit/supabase/hooks/use-sign-out';
 import { useUser } from '@kit/supabase/hooks/use-user';
 import { Button } from '@kit/ui/button';
+import { ModeToggle } from '@kit/ui/mode-toggle';
 import { Trans } from '@kit/ui/trans';
 
 import featuresFlagConfig from '~/config/feature-flags.config';
@@ -55,10 +56,18 @@ function SuspendedPersonalAccountDropdown(props: { user: User | null }) {
 
 function AuthButtons() {
   return (
-    <div className={'hidden space-x-2 lg:flex'}>
+    <div className={'hidden space-x-0.5 lg:flex'}>
+      <ModeToggle />
+
+      <Link href={pathsConfig.auth.signIn}>
+        <Button variant={'link'}>
+          <Trans i18nKey={'auth:signIn'} />
+        </Button>
+      </Link>
+
       <Link href={pathsConfig.auth.signUp}>
-        <Button variant={'outline'}>
-          <Trans i18nKey={'auth:signUp'} />
+        <Button className={'rounded-full'}>
+          <Trans i18nKey={'auth:getStarted'} />
           <ChevronRight className={'h-4'} />
         </Button>
       </Link>