merge page settings into Page tab and remove Settings tab

Custom page settings (title, slug, meta, published, navigation) now
appear as a collapsible section at the top of the Page tab. The
separate Settings tab has been fully removed.

- Add page_settings_section component to page_renderer.ex
- Remove dead :settings case from editor_panel_content
- Delete settings_editor.ex component entirely
- Remove SettingsEditor import from shop_components.ex
- Add .page-settings-* CSS styles
- Clean up old .settings-* CSS styles

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

lib/berrypod_web/components/shop_components.ex

@@ -10,7 +10,6 @@ defmodule BerrypodWeb.ShopComponents do
   - `Product` — product cards, gallery, variant selector, hero sections
   - `Content` — rich text, responsive images, contact form, reviews
   - `ThemeEditor` — shared theme editor components for admin and on-site editing
-  - `SettingsEditor` — shared settings editor components for on-site editing
   """
 
   defmacro __using__(_opts \\ []) do
@@ -20,7 +19,6 @@ defmodule BerrypodWeb.ShopComponents do
       import BerrypodWeb.ShopComponents.Content
       import BerrypodWeb.ShopComponents.Layout
       import BerrypodWeb.ShopComponents.Product
-      import BerrypodWeb.ShopComponents.SettingsEditor
       import BerrypodWeb.ShopComponents.ThemeEditor
     end
   end