feat: Custom attribute sidebar list UX improvements (#9070)

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Co-authored-by: Pranav <pranav@chatwoot.com>
Co-authored-by: Muhsin Keloth <muhsinkeramam@gmail.com>

app/javascript/dashboard/i18n/locale/en/contact.json

@@ -296,6 +296,8 @@
     "BUTTON": "Add custom attribute",
     "NOT_AVAILABLE": "There are no custom attributes available for this contact.",
     "COPY_SUCCESSFUL": "Copied to clipboard successfully",
+    "SHOW_MORE": "Show all attributes",
+    "SHOW_LESS": "Show less attributes",
     "ACTIONS": {
       "COPY": "Copy attribute",
       "DELETE": "Delete attribute",