feat: add dynamic variant selector with color swatches

- Fix Printify options parsing (Color/Size were swapped)
- Add extract_option_types/1 for frontend display with hex colors
- Filter option types to only published variants (not full catalog)
- Track selected variant in LiveView with price updates
- Color swatches for color-type options, text buttons for size
- Disable unavailable combinations
- Add startup recovery for stale sync status

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

lib/simpleshop_theme_web/components/page_templates/pdp.html.heex

@@ -44,8 +44,27 @@
       <.product_gallery images={@gallery_images} product_name={@product.name} />
 
       <div>
-        <.product_info product={@product} />
-        <.variant_selector label="Size" options={["S", "M", "L", "XL"]} />
+        <.product_info product={Map.put(@product, :price, @display_price)} />
+
+        <%!-- Dynamic variant selectors --%>
+        <%= for option_type <- @option_types do %>
+          <.variant_selector
+            option_type={option_type}
+            selected={@selected_options[option_type.name]}
+            available={@available_options[option_type.name] || []}
+            mode={@mode}
+          />
+        <% end %>
+
+        <%!-- Fallback for products with no variant options --%>
+        <div
+          :if={@option_types == []}
+          class="mb-6 text-sm"
+          style="color: var(--t-text-secondary);"
+        >
+          One size
+        </div>
+
         <.quantity_selector quantity={@quantity} in_stock={@product.in_stock} />
         <.add_to_cart_button />
         <.trust_badges :if={@theme_settings.pdp_trust_badges} />