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/_foundation-custom.scss

@@ -20,15 +20,6 @@ select {
   margin-left: var(--space-normal);
 }
 
-.tooltip {
-  background-color: var(--black-transparent);
-  border-radius: $space-smaller;
-  font-size: $font-size-mini;
-  max-width: var(--space-giga);
-  padding: $space-smaller $space-small;
-  z-index: 999;
-}
-
 code {
   border: 0;
   font-family: 'ui-monospace', 'SFMono-Regular', 'Menlo', 'Monaco', 'Consolas',