add SEO enhancements: OG images, meta robots, FAQ block, image sitemap

- Per-page SEO controls: meta robots directives, focus keyword, OG image
- Site-wide default OG image in admin settings
- FAQ block type with FAQPage JSON-LD schema
- Enhanced Organization JSON-LD with business info, contact, address
- Image sitemap with product images
- SEO preview panel with Google/social card mockups
- SEO checklist with real-time scoring
- Business info section in site editor
- GSC integration scaffolding (OAuth, client, cache)

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

lib/berrypod_web/site_editor_state.ex

@@ -26,7 +26,7 @@ defmodule BerrypodWeb.SiteEditorState do
       state = SiteEditorState.revert(state)
   """
 
-  alias Berrypod.Site
+  alias Berrypod.{Settings, Site}
   alias Berrypod.Site.{NavItem, SocialLink}
 
   defstruct [
@@ -37,6 +37,8 @@ defmodule BerrypodWeb.SiteEditorState do
     :footer_about,
     :footer_copyright,
     :show_newsletter,
+    # Business info (stored in Settings as JSON)
+    :business_info,
     # List fields (separate tables)
     :header_nav,
     :footer_nav,
@@ -52,6 +54,7 @@ defmodule BerrypodWeb.SiteEditorState do
           footer_about: String.t(),
           footer_copyright: String.t(),
           show_newsletter: boolean(),
+          business_info: map(),
           header_nav: [NavItem.t()],
           footer_nav: [NavItem.t()],
           social_links: [SocialLink.t()],
@@ -67,6 +70,7 @@ defmodule BerrypodWeb.SiteEditorState do
     header_nav = Site.list_nav_items(:header)
     footer_nav = Site.list_nav_items(:footer)
     social_links = Site.list_social_links()
+    business_info = Settings.get_business_info()
 
     state = %__MODULE__{
       announcement_text: settings.announcement_text,
@@ -75,6 +79,7 @@ defmodule BerrypodWeb.SiteEditorState do
       footer_about: settings.footer_about,
       footer_copyright: settings.footer_copyright,
       show_newsletter: settings.show_newsletter,
+      business_info: business_info,
       header_nav: header_nav,
       footer_nav: footer_nav,
       social_links: social_links
@@ -102,6 +107,14 @@ defmodule BerrypodWeb.SiteEditorState do
     Map.put(state, field, value)
   end
 
+  @doc """
+  Update a business info field. Returns updated state.
+  """
+  @spec put_business_info(t(), String.t(), any()) :: t()
+  def put_business_info(%__MODULE__{business_info: info} = state, key, value) do
+    %{state | business_info: Map.put(info, key, value)}
+  end
+
   @doc """
   Add a new social link. Returns updated state.
   """
@@ -255,6 +268,11 @@ defmodule BerrypodWeb.SiteEditorState do
       state.show_newsletter
     )
 
+    # Save business info if changed
+    if state.business_info != state._original.business_info do
+      Settings.put_business_info(state.business_info)
+    end
+
     # Sync nav items and social links
     header_nav = sync_nav_items(state.header_nav, state._original.header_nav)
     footer_nav = sync_nav_items(state.footer_nav, state._original.footer_nav)
@@ -278,6 +296,7 @@ defmodule BerrypodWeb.SiteEditorState do
         footer_about: original.footer_about,
         footer_copyright: original.footer_copyright,
         show_newsletter: original.show_newsletter,
+        business_info: original.business_info,
         header_nav: original.header_nav,
         footer_nav: original.footer_nav,
         social_links: original.social_links
@@ -301,6 +320,7 @@ defmodule BerrypodWeb.SiteEditorState do
       footer_about: state.footer_about,
       footer_copyright: state.footer_copyright,
       show_newsletter: state.show_newsletter,
+      business_info: state.business_info,
       header_nav: Enum.map(state.header_nav, &nav_item_snapshot/1),
       footer_nav: Enum.map(state.footer_nav, &nav_item_snapshot/1),
       social_links: Enum.map(state.social_links, &social_link_snapshot/1)