consolidate shop pages into unified LiveView for editor state persistence

Replace individual shop LiveViews with a single Shop.Page that dispatches
to page modules based on live_action. This enables patch navigation between
pages, preserving socket state (including editor state) across transitions.

Changes:
- Add Shop.Page unified LiveView with handle_params dispatch
- Extract page logic into Shop.Pages.* modules (Home, Product, Collection, etc.)
- Update router to use Shop.Page with live_action for all shop routes
- Change navigate= to patch= in shop component links
- Add maybe_sync_editing_blocks to reload editor state when page changes
- Track editor_page_slug to detect cross-page navigation while editing
- Fix picture element height when hover image disabled
- Extract ThemeEditor components for shared use

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

lib/berrypod_web/page_editor_hook.ex

@@ -31,6 +31,7 @@ defmodule BerrypodWeb.PageEditorHook do
       # Page editing state
       |> assign(:editing, false)
       |> assign(:editing_blocks, nil)
+      |> assign(:editor_page_slug, nil)
       |> assign(:editor_dirty, false)
       |> assign(:editor_at_defaults, true)
       |> assign(:editor_history, [])
@@ -67,13 +68,81 @@ defmodule BerrypodWeb.PageEditorHook do
     {:cont, socket}
   end
 
-  # ── handle_params: track current path ────────────────────────────
+  # ── handle_params: track current path and restore editor state ────
 
-  defp handle_editor_params(_params, uri, socket) do
+  defp handle_editor_params(params, uri, socket) do
     parsed = URI.parse(uri)
 
-    # Store the current path for reference (e.g. the Done button)
-    {:cont, assign(socket, :editor_current_path, parsed.path)}
+    socket =
+      socket
+      |> assign(:editor_current_path, parsed.path)
+      |> maybe_restore_editor_state(params)
+
+    {:cont, socket}
+  end
+
+  # Restore editor state from URL params on navigation
+  # Only activates state if not already in the requested state (avoids loops)
+  defp maybe_restore_editor_state(socket, params) do
+    if socket.assigns.is_admin do
+      requested_tab = params["edit"]
+      current_tab = socket.assigns.editor_active_tab
+      current_state = socket.assigns.editor_sheet_state
+
+      # If already in the correct state, don't re-apply
+      already_correct? =
+        current_state == :open && requested_tab &&
+          String.to_existing_atom(requested_tab) == current_tab
+
+      if already_correct? do
+        socket
+      else
+        case requested_tab do
+          "theme" ->
+            socket
+            |> assign(:editor_sheet_state, :open)
+            |> assign(:editor_active_tab, :theme)
+            |> maybe_enter_theme_mode()
+
+          "page" ->
+            socket
+            |> assign(:editor_sheet_state, :open)
+            |> assign(:editor_active_tab, :page)
+            |> maybe_enter_page_mode()
+
+          "settings" ->
+            socket
+            |> assign(:editor_sheet_state, :open)
+            |> assign(:editor_active_tab, :settings)
+            |> maybe_enter_theme_mode()
+
+          _ ->
+            socket
+        end
+      end
+    else
+      socket
+    end
+  end
+
+  defp maybe_enter_theme_mode(socket) do
+    if socket.assigns.theme_editing do
+      socket
+    else
+      load_theme_state(socket)
+    end
+  end
+
+  defp maybe_enter_page_mode(socket) do
+    if socket.assigns.editing do
+      socket
+    else
+      if socket.assigns[:page] do
+        enter_edit_mode(socket)
+      else
+        socket
+      end
+    end
   end
 
   # ── handle_info ─────────────────────────────────────────────────
@@ -703,6 +772,7 @@ defmodule BerrypodWeb.PageEditorHook do
     socket
     |> assign(:editing, true)
     |> assign(:editing_blocks, page.blocks)
+    |> assign(:editor_page_slug, page.slug)
     |> assign(:editor_dirty, false)
     |> assign(:editor_at_defaults, at_defaults)
     |> assign(:editor_history, [])
@@ -725,6 +795,7 @@ defmodule BerrypodWeb.PageEditorHook do
     socket
     |> assign(:editing, false)
     |> assign(:editing_blocks, nil)
+    |> assign(:editor_page_slug, nil)
     |> assign(:editor_dirty, false)
     |> assign(:editor_history, [])
     |> assign(:editor_future, [])