feat: Add new sidebar for Chatwoot V4 (#10291)

This PR has the initial version of the new sidebar targeted for the next major redesign of the app. This PR includes the following changes

- Components in the `layouts-next` and `base-next` directories in `dashboard/components`
- Two generic components `Avatar` and `Icon`
- `SidebarGroup` component to manage expandable sidebar groups with nested navigation items. This includes handling active states, transitions, and permissions.
- `SidebarGroupHeader` component to display the header of each navigation group with optional icons and active state indication.
- `SidebarGroupLeaf` component for individual navigation items within a group, supporting icons and active state.
- `SidebarGroupSeparator` component to visually separate nested navigation items. (They look a lot like header)
- `SidebarGroupEmptyLeaf` component to render empty state of any navigation groups.

----

Co-authored-by: Pranav <pranav@chatwoot.com>
Co-authored-by: Pranav <pranavrajs@gmail.com>

app/javascript/dashboard/composables/utils/useKbd.js

@@ -0,0 +1,22 @@
+import { computed } from 'vue';
+
+export function useKbd(keys) {
+  const keySymbols = {
+    $mod: navigator.platform.includes('Mac') ? '⌘' : 'Ctrl',
+    shift: '⇧',
+    alt: '⌥',
+    ctrl: 'Ctrl',
+    cmd: '⌘',
+    option: '⌥',
+    enter: '↩',
+    tab: '⇥',
+    esc: '⎋',
+  };
+
+  return computed(() => {
+    return keys
+      .map(key => keySymbols[key.toLowerCase()] || key)
+      .join('')
+      .toUpperCase();
+  });
+}