Pre-launch design sync with Figma spec (#2154)

* Add lookbook + viewcomponent, organize design system file

* Build menu component

* Button updates

* More button fixes

* Replace all menus with new ViewComponent

* Checkpoint: fix tests, all buttons and menus converted

* Split into Link and Button components for clarity

* Button cleanup

* Simplify custom confirmation configuration in views

* Finalize button, link component API

* Add toggle field to custom form builder + Component

* Basic tabs component

* Custom tabs, convert all menu / tab instances in app

* Gem updates

* Centralized icon helper

* Update all icon usage to central helper

* Lint fixes

* Centralize all disclosure instances

* Dialog replacements

* Consolidation of all dialog styles

* Test fixes

* Fix app layout issues, move to component with slots

* Layout simplification

* Flakey test fix

* Fix dashboard mobile issues

* Finalize homepage

* Lint fixes

* Fix shadows and borders in dark mode

* Fix tests

* Remove stale class

* Fix filled icon logic

* Move transparent? to public interface

app/views/chats/_chat_nav.html.erb

@@ -13,12 +13,23 @@
     </div>
   </div>
 
-  <%= contextual_menu icon: "more-vertical", id: "chat-menu" do %>
-    <%= contextual_menu_item "Start new chat", url: new_chat_path, icon: "plus" %>
+  <%= render MenuComponent.new(icon_vertical: true) do |menu| %>
+    <% menu.with_item(variant: "link", text: "Start new chat", href: new_chat_path, icon: "plus") %>
 
     <% unless chat.new_record? %>
-      <%= contextual_menu_item "Edit chat title", url: edit_chat_path(chat, ctx: "chat"), icon: "pencil", turbo_frame: dom_id(chat, "title") %>
-      <%= contextual_menu_destructive_item "Delete chat", chat_path(chat), turbo_confirm: "Are you sure you want to delete this chat?" %>
+      <% menu.with_item(
+        variant: "link",
+        text: "Edit chat title",
+        href: edit_chat_path(chat, ctx: "chat"),
+        icon: "pencil", data: { turbo_frame: dom_id(chat, "title") }) %>
+
+      <% menu.with_item(
+        variant: "button",
+        text: "Delete chat",
+        href: chat_path(chat),
+        icon: "trash-2",
+        method: :delete,
+        confirm: CustomConfirm.for_resource_deletion("Chat")) %>
     <% end %>
   <% end %>
 </nav>