feat: Add support for dark mode in dashboard (#7460)

- Add config for TailwindCSS
- Enable HMR
- Add a config in LocalStorage for Dark Mode

Co-authored-by: Pranav Raj S <pranav@chatwoot.com>

app/javascript/dashboard/assets/scss/_rtl.scss

@@ -3,9 +3,6 @@
 
   // Primary sidebar
   .primary--sidebar {
-    border-left: 1px solid var(--s-50);
-    border-right: 0;
-
     .options-menu.dropdown-pane {
       right: var(--space-smaller);
 
@@ -42,15 +39,6 @@
         margin-right: unset;
       }
 
-      .account-context--group .account-context--switch-group {
-        --overlay-shadow: linear-gradient(
-          to left,
-          rgba(255, 255, 255, 0) 0%,
-          rgba(255, 255, 255, 1) 50%
-        );
-        background-image: var(--overlay-shadow);
-      }
-
       // Help center sidebar
       .sidebar-header--wrap .header-title--wrap {
         margin-left: unset;