improve lighthouse scores: image priority and long-poll removal

- Add priority attr to product_card, thread through to responsive_image
- First 2 featured products get fetchpriority="high" and eager loading
- Remove longPollFallbackMs to avoid unnecessary fallback attempt

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

assets/js/app.js

@@ -286,7 +286,6 @@ const Lightbox = {
 
 const csrfToken = document.querySelector("meta[name='csrf-token']").getAttribute("content")
 const liveSocket = new LiveSocket("/live", Socket, {
-  longPollFallbackMs: 2500,
   params: {_csrf_token: csrfToken},
   hooks: {...colocatedHooks, ColorSync, Lightbox, CartPersist, CartDrawer},
 })

lib/simpleshop_theme_web/components/shop_components/product.ex

@@ -35,6 +35,7 @@ defmodule SimpleshopThemeWeb.ShopComponents.Product do
   attr :show_badges, :boolean, default: nil
   attr :show_delivery_text, :boolean, default: nil
   attr :clickable, :boolean, default: nil
+  attr :priority, :boolean, default: false
 
   def product_card(assigns) do
     # Apply variant defaults for nil values
@@ -71,6 +72,7 @@ defmodule SimpleshopThemeWeb.ShopComponents.Product do
             product={@product}
             theme_settings={@theme_settings}
             variant={@variant}
+            priority={@priority}
             show_category={@show_category_resolved}
             show_badges={@show_badges_resolved}
             show_delivery_text={@show_delivery_text_resolved}
@@ -86,6 +88,7 @@ defmodule SimpleshopThemeWeb.ShopComponents.Product do
             product={@product}
             theme_settings={@theme_settings}
             variant={@variant}
+            priority={@priority}
             show_category={@show_category_resolved}
             show_badges={@show_badges_resolved}
             show_delivery_text={@show_delivery_text_resolved}
@@ -101,6 +104,7 @@ defmodule SimpleshopThemeWeb.ShopComponents.Product do
           product={@product}
           theme_settings={@theme_settings}
           variant={@variant}
+          priority={@priority}
           show_category={@show_category_resolved}
           show_badges={@show_badges_resolved}
           show_delivery_text={@show_delivery_text_resolved}
@@ -113,6 +117,7 @@ defmodule SimpleshopThemeWeb.ShopComponents.Product do
   attr :product, :map, required: true
   attr :theme_settings, :map, required: true
   attr :variant, :atom, required: true
+  attr :priority, :boolean, default: false
   attr :show_category, :boolean, required: true
   attr :show_badges, :boolean, required: true
   attr :show_delivery_text, :boolean, required: true
@@ -126,6 +131,7 @@ defmodule SimpleshopThemeWeb.ShopComponents.Product do
       <.product_card_image
         product={@product}
         variant={@variant}
+        priority={@priority}
         class="product-image-primary w-full h-full object-cover transition-opacity duration-300"
       />
       <%= if @theme_settings.hover_image && @product[:hover_image_url] do %>
@@ -163,6 +169,7 @@ defmodule SimpleshopThemeWeb.ShopComponents.Product do
   # Requires source_width to be set for responsive image support.
   attr :product, :map, required: true
   attr :variant, :atom, required: true
+  attr :priority, :boolean, default: false
   attr :class, :string, default: ""
   attr :image_key, :atom, default: :primary
 
@@ -203,7 +210,7 @@ defmodule SimpleshopThemeWeb.ShopComponents.Product do
         class={@class}
         width={600}
         height={600}
-        priority={@variant == :minimal}
+        priority={@priority}
       />
     <% else %>
       <img
@@ -211,8 +218,8 @@ defmodule SimpleshopThemeWeb.ShopComponents.Product do
         alt={@product.name}
         width="600"
         height="600"
-        loading={if @variant == :minimal, do: nil, else: "lazy"}
-        decoding={if @variant == :minimal, do: nil, else: "async"}
+        loading={if @priority, do: nil, else: "lazy"}
+        decoding={if @priority, do: nil, else: "async"}
         class={@class}
       />
     <% end %>
@@ -715,12 +722,13 @@ defmodule SimpleshopThemeWeb.ShopComponents.Product do
       </h2>
 
       <.product_grid theme_settings={@theme_settings}>
-        <%= for product <- Enum.take(@products, @limit) do %>
+        <%= for {product, idx} <- @products |> Enum.take(@limit) |> Enum.with_index() do %>
           <.product_card
             product={product}
             theme_settings={@theme_settings}
             mode={@mode}
             variant={:featured}
+            priority={idx < 2}
           />
         <% end %>
       </.product_grid>